Your not crazy.
Terrible for sure..some of it is already pulling away already anyway.With the mud so thick and already hardened with mesh tape in it you can't even sand your way out of that nightmare. Joecaptions pretty spot on with my opinion.
Almost certain the guys hired would just try to throw mud and sanding blocks at it until it looked halfway okay but even then it wouldn't be close to right.
Find a new installer, or diy either way I'd redo the whole thing, with all the pieces and the way they have done things It's probably not fastened properly either and even if you did a miracle mud job on it, given a little time cracks would be appearing.
I agree. I could have done a better job myself- I just think they are idiots+1 on a total re-do. I haven't seen work that bad in 20 years!!! Even someone with rudimentary drywall skills, with the help of some YouTube videos, could do a passable job. That is not remotely passable.