Ofc they do, because it attracts more people aka they make more money.
But thats also the way you should take the game, just not to serious. Its cool to kill time and sometimes you can have a blast with your own deck when some plan works out well.
I mean i never passed rank 10, but i really dont see the point why i should invest time to have a good rank. It just doesnt feel rewarding enough to be "good".
But after all i invest still a lot of time in just being shit somewhere between rank 10-15, by switching decks every like 3 games