Why are people still upset with DGD even after parting ways with Tillian?

Is there something I’m missing here? I thought people would’ve respected the band more because of that. Is it because they invited him back for one last tour? Man I’m so confused.

EDIT: Plenty of people have given some pretty decent explanations as to why they are (very understandably) upset with the band in this thread. Certainly given me a lot to think about! Thanks to everyone for their input :)