if you actually think "blockland doesn't need updates to stay popular" you're mad.
if roblox was the exact same game+website that it was back in 2010, would it still be popular today? of course not. roblox still thrives today because theres constant development and updates to the game - its basically an entirely new game compared to what it was years ago.
blockland has been literally the exact same game as it has been since, like, 2013. sure there's been a bunch of new revolutionary add-ons, but add-ons can only do so much before the true restrictions of a engine from 2004 starts to show. this is why it's now just slowly dying off - with badspot clearly being done with the game, many other developers have also accepted this same fate and have abandoned the game too. we're now at the loving desperate times of injecting dlls into the game to get anything new out of it and even then it's becoming more and more boring.
a game like this can be considered 'done', sure. but you cannot expect a 'finished' game to still have an active community after this many years.