Without a trusted third party doing something like this on a large scale, it doesn't really matter - because 'nah, that's just a fake.'
My wife and I were recently talking about how we kind of luck boxed into dodging a bullet when we had kids (which was rather late). But it's no wonder so many people had or are having so many issues growing up in a public social media era. It's not only your right, but responsibility, to say, believe, and generally do stupid things as a kid and a young adult. It's an important part of growing up. Nobody should ever have to worry about this period in their life following them around forever.
> it doesn't really matter - because 'nah, that's just a fake.'
The point of this sort of thing is that whether it is fake or not doesn't matter. Because it is possible for someone to record a log of your activities, someone claiming they have an incriminating log of your activities will be believed (By a very large number of people).
It might not be believed in a courtroom, but for the other 99.99% of life, we do not apply the same standards for reviewing evidence.
Whether the platform keeps logs isn't important - the platform won't weigh in on this sort of stuff anyways, unless there's a subpoena.