Is it really THAT bad?

No, it's not bad. The story doesn't completely work, but there are some cute moments and a couple laughs. I rated it a 6/10.

It is okay for what it is.

It can’t possibly be worse than the bill murray version

The first 4 minutes are what I think I would have wanted in a Garfield film. Then it's a bunch of random nonsense. Prepare to watch 7 new characters get introduced and get "heartfelt" moments.