I’m for it. A lot adults don’t want to “get involved in politics” or stick to their party due to loyalty rather than caring about the outcome. 16 year olds are a lot more politically aware than adults realise, not enough credit is given to them. Yes they are immature in a lot of senses, but aren’t we all in some ways? The ones that don’t care simply won’t vote. The ones that do care deserve to have their voices heard.
Whether or not someones brain is developed and their competency isn’t taken into account for adults, so this is a rubbish point against teenagers. And as has been mentioned many times, it’s their future. It shouldn’t just be up to pensioners and parents to decide.