Outside of launch periods more niche games like Darktide, Tribes etc are reduced to a small core of regulars at best and are completely dead at worst.
Days after the launch of Dawn of War 3 I couldn’t find any OCE players… granted it was far more dead on arrival than the majority of games. And yes obligatory DoW3 was trash.
Big games and franchises are fine and I even host several servers with decent sized communities myself, (currently) Palworld, Project Zomboid and Minecraft.