From what I've heard you get a mission, fly to said mission, complete said mission, go back to Tarsis, rinse lather repeat. The going back to town after each mission, not being able to change loadouts on the fly, and sameish looking enemies, and the meh loot, makes the experience too much of a grind.
I've also heard the story is lukewarm at best and there's no real sense of progression. People have complained about the pacing of the story and how the awkward interactions between characters often seem forced and unemotional.
The absolute worst thing I've heard about the game is that it's just a little better than Destiny 2.
I have heard that small improvements have been made but I can't jump in yet. A great story (or great loot) can make up for an excessive grind or satisfying gameplay can make up for a tepid story (Call of Duty, Borderlands). I think Anthem would fall in the latter scenario IF the grind or loot progression got addressed.
My fear is that if I pick it up now it'll fall in with games like Titanfall, Destiny, Halo 5, etc. that I was really excited for but found them just to be ok. Each may have been played a couple hours and sit on the shelf. I'll grab those kinds of games up during the $10 black Friday or amazon sales.