Yeah, the early reviews really did not help with this. With a large franchise reviews are not that important, but something like Alita really can be damaged quite a bit. Especially if the bad reviews come in early (this started in the low 30ties).
I have tried finding a movie that has a similar top critics/critics difference as Alita and was not able to (27% points)... it really got trashed by a lot of early (major) outlets.
Aside from that yeah, the budget is a bit of a problem, but at least every penny of that is visible on screen.