That's not the point, yes they're relatively easy to play around but the proliferation of them has shaped the meta in a way that has made a lot of decks no longer viable. Pre Sylvans it was really varied and you saw a lot of originality now it's Sylvans, DH or CA 8 or 9 times out of ten and for f2p players it can be difficult to build a deck that can consistently beat all of them.
If you need to make a deck anti-sylvan... you understand isn't a good point.
People don't want to build a deck for counter any other; people want to have some chances to duel with your own valid deck.
Sylvan deck get out from this balance purpose.
Sylvan deck does in a turn only everything any other deck can do after 3 turns.
While i dont mind sylvan (heck i reached legend first time this season cuz sylvan only have 1 trick...) the amount of sylvan deck out there is too damn much. I have no patient for pvp as it is and playing with the same deck everytime is horrid