Congrats on getting clean; that's an incredible achievement. Even though I am not too old myself, I really resonate with your experience of maturing and looking back at past versions of yourself. I don't remember when, but I stumbled across your previous post back before I used an account, and your optimism (especially in the update) really helped me move past some struggles in my own life. Thank you for that.
As for how Newgrounds has changed, I'd say it's simultaneously become more mature and less mature at the same time. While I wasn't on the site in the early 2000's, I was here (on and off) throughout the 2010's. At least from my observations, the older users that stuck around matured up, and a very immature group of Friday Night Funkin' and Geometry Dash fans spawned beneath them, creating this awkward divide of maturity and hyper-immaturity. I haven't really had issues with slurs and bigotry, and when they do show up, they're usually removed pretty quickly.
If you want to see how any of the rules have changed, take a look through the guidelines of art, music, reviews, etc.
Glad to see you're still around.
xeiavica
I don't know if the mods were more strict back then, but if the BBS supporter forum is to be any indication, it's gotten more lenient on what threads are allowed. Take a good look at a wegra or drunkgecko thread and you'll see what I mean.
Thetatronica
I came up on here in the 2000/2001 days of racial slurs, school shooter games, hentai games and all the other insanity that was common, so it was quite a different place when I used to actually frequent it. I just figured since it was starting to be more censored back when I made the post 12 years ago, I imagine it's probably even more censored now.