They’re absolutely losing more than 10% of their playerbase every expansion.
This game is an absolute ghost town compared to what it was at the height of Legion. Give it another 5 years and matchmaking queues are going to be stuck in perpetual “search” mode.
But hey, the people that are hopelessly addicted to these obscene grinds/chores aren’t people using those systems anyways, so I guess no big deal.