Myth of Cambridge admissions being just merit based - Mainly international students

I think this generalisation is a bit unfair. I understand your frustrations but Cambridge can only do so much.
Also... "richer students from the bottom of the admissions ranks" is an ignorant comment. Every single applicant who is ABLE to even apply to Oxbridge will have the grades, the enthusiasm etc. Each one is just as capable as the next. Oxbridge and other unis often state that they have to turn away and reject A MYRIAD of capable and amazing applicants each year. Just because someone is born wealthy, does not indicate that they aren't smart or aren't worthy of an offer.
And of course they'd have to accept more UK citizens...they're an English uni. Furthermore, Cambridge IS trying to widen their accessibility rates... they take contextual and extenuating circumstances into consideration and they don't seem to (at least from what I've seen) discriminate against state students as much as Oxbridge used to. Of course this is indeed mostly for home students. However, any sane uni will not accept more internationals than home students, that would be preposterous and they would be called out for it. That is why the requirements for intl students are so high and demanding. This is also why the same considerations that are given to home students cannot be offered to intl students.
Anywho, nobody can go to uni if they cannot fund it. Higher education is a PRIVILEGE, it is not owed to you. Neither is a scholarship. It's the harsh and sad reality. While this is indeed unfortunate, you cannot pin the blame solely on Cambridge. Also you mentioned that for international students, there are no student loans available hence Cambridge is lying to you. Firstly, Cambridge DOES try its hardest to help students if they are facing financial difficulties. Of course they give out offers based on academics only. Whether you can afford it or not is a YOU problem, but like I said, Cambridge does try its best to help currently enrolled students. Secondly, is this not the case for every single UK uni? For everyone international student? No international student is able to get a student loan from the government. It doesn't matter whether you're applying to Oxbridge or idk, Uni of East London, you should know that studying abroad comes with a lot of risks and responsibilities. And you should be prepared for them. That's why most people choose NOT to study abroad. Studying abroad is even MORE of a privilege than obtaining higher education. People don't apply to study abroad if they know that they cannot afford it. You cannot expect a uni to cater to everyone.
Lastly, I'm pretty sure there is a scholarship for international students only. Ofc there's a lot of competition for it but one does exist. There are plenty of other funding methods too. There are choir scholarships, music, sport, research etc. Ofc they're not gargantuan amounts, but they do exist.
One more thing, while Oxbridge is indeed quite rich, you have to keep in mind that coddling undergraduates is not their sole purpose. They have to fund world-changing research, pay the thousands of staff, maintain and upkeep the massive site etc. I would argue they would much rather fund postgraduates undertaking critical research than a puny undergraduate who doesn't know what they want to do with life yet. I apologise with how harsh I'm speaking, but if you really think about it, it is indeed the cold reality.
Life is unfair. And we all know it. I empathise with you; it's so frustrating not being able to attend your dream uni or widen your opportunities because of reasons out of your control. However, please know that complaining will not change a thing. The only thing you can change is yourself and how you perceive things. Sometimes if a path is blocked in life, there will always be another path. No matter how much worse off the second path is, as long as you're ambitious enough, and work hard enough, you'll make it to where you're supposed to be. I'm sure we'd all rather have been born in a family with generational wealth, but we weren't. So the only thing we can do is work hard and try our best take the opportunities you get with a smile, see off the opportunities you do not get also with a smile. That's the joy of life.
Now, I feel like a Dumbo. I apologise for writing a mini essay. I wish you the best with your future endeavours. Rejection is redirection, NO means a New Opportunity, and you never know where you'll be led to next. Best wishes.

Hello, just to clarify,
In terms of the first point, I mean as per the rankings university itself gives to applicant, based on how they expect them to achieve.
In terms of unis not accepting more internationals than home students, it seems some unis got into a loop of doing this as they started mainly accepted international students due to them being a source of funding, but this largely depends and isn't true for medicine.
In terms of this being this way for every single uni, this is true, but there are two major differences between oxbridge and the rest, the fact oxbridge has way more capital and the fact they directly say in multiple places that they'll make sure you can come to Oxbridge no matter your financial situation, not mentioning this only holds for home students. I do see it may not be financially viable but they should be honest.
In terms of taking loans, some countries do actually offer ability to take student loans even to study abroad.
Fortunately I myself am likely not actually to be affected by this, as I am not an international student, just writing based on knowing some international people who struggle with money, and the fact the undergrad pages make it seem like that's not gonna be an issue, quoting Oxford for example, "Oxford is committed to ensuring that all students who are offered a place to study here can afford to come.” Where they don't mention this isn't the case for International students, and neither do they in alumni videos asking for more money, or if you ask them at open days. At the end of the day, if it's not financially viable, for the people who need it either as a bursary or a loan, I wish they were more direct about it.