Yes it is. Sadly, making it free to play was probably their biggest mistake because the major part of the free to play audience is represented by casual/normal players, while due to the deep and obscure game mechanics, Let it Die target is pretty much hardcore.
Some say the game is locked behind a paywall but trust me, this is only true for people that try to rush the game and not understanding the rules, are getting severely punished.
This is not for everyone but give it a try and let me know.