There's nothing like this if you want to play tanks even though it's a little old, has steep learning curve, slow grinding unless buying premium account and most notoriously poor and poorer balance in matching making. For me, playing for free for Tier 8 and below is very possible, for Tier 9 it will be frustrating and for Tier 10 it's almost impossible to last. Tier 9 and 10 are where most fun resides. So in general, as content creator Skill4ltu pointed out, Tier 9 is the sweet spot of the game.
They need to make money, though I think the premium account is too expensive.