I don't feel like sG has "gone downhill" or anything, the priorities just shifted.
When I first joined, I feel that most the community was based off of our gaming servers, like for me it was GMod TTT, then I played some JB and TTTGO as well. While others did Surf, War3 (i think thats what it was called), etc.
Now and days, sG is more of just a community of playing different various games together and talking on discord.
I do miss the constant forum shit talking and servers, but for me I kind of just transitioned into playing games mostly with my IRL friends.
But someone hit me up if GMod TTT or the "new sandbox" game ever comes out with a server