I think there's a strong possibility you're correct, especially with that genre. When it comes to purely competitive games continual new content and adjustments keep the masses coming back, and providing those things long term with no monetization is a business suicidal idea, and I think that strong reasoning like that excuses a lot of the cynicism and bad faith behind MTX in those specific cases provided its still relatively fair.

I give you an A+ for an actual strong argument for MTX (in those and related cases)