I've done a fair amount of searching and can't find a straight answer anywhere.
What bothers me most is how hard it is to find real, unfiltered opinions on this stuff. Forums like this are honestly more useful than any best-of list I've found through searching.
I've noticed a huge difference between platforms that moderate actively and those that don't. The ones that don't tend to become unusable within a few months.
Feel free to share whatever has worked for you, even if it's not the obvious answer.