Lack of updates, Lack of media, lack of mobile support. These three things kinda killed it.
I contend that technological limits really did Blockland in. Being stuck as a 32-bit application with only single-core optimization really kneecaps a program across the 2010s and beyond. As someone who also loves to work with Events, and probably still would if I were to return, I was also held back by concurrent events limits which made highly interactive worlds impossible. The technological limits of Blockland played a large part of why I left, or rather, why Blockland more or less chose proverbial curtains for me.
Design choices such as Shaders XOR Terrains+Interiors has been critiqued to the moon and back already by people far more knowledgeable than I am, to an extent far better than I can.
As many have said before, marketing the game to children in the combination of not having moderation features was a mistake. If it were moderated to the extent that it was but was marketed to young adults, you would still see the usual Drama topics about the individual problem users, but I find it neither likely that issues of this kind would become endemic, nor metastasize into this kind of topic.
Despite the toxicity, I really did have over a decade of awesome moments on this game, met some amazing people. When Mac support dropped 32-bit applications on my only computer, my tenure on Blockland the game just about came to an end. I have another computer now that can run it, but the lights are off, and no one seems to be around, so I'm left scratching my head thinking what the point is. If the community was as vibrant as it was in 2019 when I still could hop on and have some cool moments, I think I would still consider booting up the game, but it feels like with all the servers there are competing for so few players, I couldn't really put together the large projects that I wanted to make, that required large teams in TDMs or tournament-style Colosseum matches.
So maybe someday. But I'm not counting on it.
Edit: Speaking of player count, if you use a JS Injector,
I made a simple script to display the player count at the top of the servers page. Use it or don't, idc; it's up to you.