I am someone who posts art somewhat regularly on Reddit, and I cansay that all of the subreddits that I posted art to has been un-private, so it's business as usual for me
Using LibreWolf right now! The experience is smooth most of the time, although you do need to switch to Firefox when you need to view DRM-controlled content (like when participating an online course, for example).
I think you can somewhat assure that most of them aren't bots, since bots get banned fairly quickly by mods of instances and most instances have systems to make sure the bot will not pass through so easily
famicase.com
Waste your time seeing custom Famicom cases that people designed.
Seriously, this website is a great place for finding inspiration, if you are like me.