This is the reason that it can’t happen. If the game is always there, then people will be less likely to play it, that’s why it’s featured, not just a main game.
That doesn't make sense if talking about the other games since those have lower player counts too, specifically minerware and parkour.
I didn't word my original post quite clearly, but I also wanted to mention the game's overall history. There's a video explaining the overall history of SG and its decline. I think this one sums it up, citing that SG's decline is related to MC's general decline in the mid-2010s.
Coincidentally, around 2016 was when CCG's SG has at least 100 players or more, if not hundreds if I recall correctly. There was an update in 2016 that revamped CCG's SG by adding new maps, changing kits, and loot; this most likely caused SG here to get some popularity. However, it was around mid-2017 when its numbers fell to <100.