The one thing I realize about questions like this is that they are simply pointless. There is very little an ordinary individual can do to alter much. Even if you got taken back in time to the right time and place to make a change, what would that look like? People write stuff that predict the future all the time. Technofascist predictions about the internet being used by a few jackasses to monitor everyone and keep people under control have been written in the 90s, but no one listened at the time.

Assassination? Good luck! Even if you got teleported back in time to 1997 and were armed with a gun and right outside a room with an unsuspecting Peter Thiel and Elon Musk (and maybe a few others) would blowing them away genuinely 'solve' the problems we have today? Or would it simply allow for another person to step in and do the same shit but just with a different name and face?

Enriching yourself using well timed lottery numbers is practically the only thing that would make things better for you, but while that would mean you can relive those years in complete comfort (even luxury) if your objective is to change the world then it is a hollow one.