Charging VAT on private school fees

It's the petty act of vindictiveness that permeates the socialists mindset. The idea that someone has something better that they have chosen and are willing to pay for - this makes socialists so hateful and jealous that their recourse is to seek to destroy it.
Because that's what it is. They know full well that the tax is meaningless. It won't raise much in terms of revenue, and will probably mean several schools closing down and a bunch of people losing their jobs - and then you'll have a few thousand kids having to go to state schools....but no extra money to facilitiate that. This is a purely punitive measure.
The idea that this is a tax-break is absurd. Following this exact rationale, there is no reason on earth not to have VAT on university fees. University, if anything is far more selective than school.

I do think that taxing private schools, and not private tutors (basically those who are as rich as private school parents that just pay for 1 to 1 tutoring) and not universities (to a lesser extent than private tutors) is grossly unfair.

PRSOM!
Universities are more selective although they do take more pupils of poorer backgrounds than almost all private schools.
Also very funny to see that about 1/4 of Labour MPs are privately educated 😂

It's worse than that. Starmer has just admitted that he accepted £20,000 to help his son with his GCSEs.

This is essentially the crux of the socialist outlook. No-one can be allowed to have anything better. This is how the old Soviet bloc used to run, and how North Korea still works. Everyone wears the same government approved clothing and the only car you can have is the one made by the state owned manufacturer. Everyone eats the same government approved slop.
Why should anyone ever be allowed to have anything that they want because they think it's better?

I wouldn't say it's exactly socialist - but definitely nasty.

The aim of this is to try and eliminate private education and leave only government schools. That is so socialist, you could stick a goatee on it and call it Lenin.

Removing private schools completely would be a huge catastrophe for the economy. People struggle to realise that the existence of private schools is doing them a massive favour.

I don't really think it's all that relevant how much private school fees have increased historically. These increases have been at the schools' discretion, and will have naturally taken into account the usual supply and demand factors: how much people can afford, what their running costs are, the number of places they can offer etc. and they have also been gradual enough to allow time for people to adjust to the changes. That's quite different from an instantaneous increase of 20% on top of what the school would otherwise be charging, which represents a far greater shock to the system.
I'd also reiterate my point that the positives of charging VAT needs to be considered in the context of what alternative ways there are to collect more taxes. Just because the VAT on private schools raises an extra billion a year or so in taxes doesn't mean this is the best way to do it, all knock-on impacts considered.
Fair point made in your second paragraph though. It depends on what exactly the parents end up spending the money that they saved on school fees on. If I were one of those parents, it would probably go on things like private tuition and getting a house in the catchment area of my preferred state school (which generally do not attract a great deal of tax), but everyone's different.

What if the child has extra needs that cannot be supported by their local state school? What if there are not sufficient places at their local state school? Even though it’s something extra, I still don’t think you can class arguably better education as a luxury. It’s not the same as going on holiday to Dubai every summer. And in any case, it should be phased in rather than introduced mid academic year to allow parents to make the choice to move their children to state schools.

For them, ideology is far more important than the economy. Also, they would just deny it and blame someone else. Probably Trump, Brexit, or "the Tories".

It's relevant if the claim is that higher fees will result in a long term exodus from private schools. We know from existing data that this isn't the case; private school fees have grown far beyond inflation while real wages have stagnated, yet private school enrollment has remained remained roughly the same. While a 20% increase would be instananeous and larger than any prior year-on-year increase, it doesn't change anything if the question is about the long term impact.

People can't just throw 10k at VAT for their 2 or 3 kids out of the blue. You act like that's insignificant money?

Evidently they can. Private school fees have risen above inflation since the 1990s and have resulted in fees being 50% higher than they would be if they matched inflation. Private school attendence hasn't gone down during that period (if anything it's slightly increased), so the conclusion is that the people who want to send their children to private schools can (in general) afford increases of that magnitude.

Stable private school pupils numbers are largely due to a significantly higher immigrant population, demographic changes and people being much more able to afford it.
You haven't addressed my point about the suddenness of the tax - 10k (now) over 30 years is not comparable to 10k over 1 year.

For them, ideology is far more important than the economy. Also, they would just deny it and blame someone else. Probably Trump, Brexit, or "the Tories".

I'm not sure that makes any sense. Real wages have not increased since 2008. If people are still able to afford private education, as evidenced by the stable enrollment rate, then all this says is that the parents of privately educated children are (in the vast majority of cases) capable of paying much higher fees than they are letting on.
I agree that a sudden 20% increase in fees is different to the year-on-year differences we have seen previously, however my point is that this will not make a different to enrollment in the long term (just as a 50% increase hasn't made any difference).
One thing you've also assumed is that private schools will pass the 20% increase on to the parents. This won't necessarily be the case.

It's rich for libertarian capitalists on the right to complain about "ideology" from "socialists" when just two years ago they crashed the economy and wasted £30 billion on a 50 day experiment. "Deny it and blame someone else" sounds very familiar.