I have played 2 matches of this now, just to try it out.
First time I went in cold - and I wanted to break something IRL from the frustration of not having a single pointer ingame as to how anything works, is connected or how to navigate. I still get popups in ARAM about "returning to base won't heal me", even after 9654 games there. In Teamfight Tactics: Nothing!
Second time, having read up a bit on it and applied thought and tactics into it, I have not been so bored in a long, long time while actually playing a game.
Nothing happened, time passed and every second of it felt wasted, and the only incentive to keep players hooked is by outright bribing them with "rewards" (emotes, icons, "beta pass" (whatever that is) etc.). It felt outright insulting.
Knowing the basics, the sheer RNG on items and champions felt like a punch in the face too.
This is a pure mobile game, and got NOTHING to do with League of Legends as the game should be played - or used to be played anyway, with actual long-game strategies instead of the second-to-second tactics we now have.