The problem was everyone on an H1B visa would work any hours, pick their phone up 24/7 etc. Effectively they were always on-call and for a lot of the local/US engineering talent we disagreed with the "always-on" culture they brought. They also contributed to that "always-on" culture by never finishing work, pushing deliverables out the door with zero security review, no documentation etc. It's also worth mentioning these budget teams of H1B "engineers" come in and create their own cyclical work by constantly fixing problems they caused. This is what happens when you treat engineering and management as a "cost center" :(
Mostly though, it was insane to hear how blatant they were with bigoted comments, like "we don't hire _those_ kind of Indians", and "if it wasn't for foreign talent we'd have none at all." I felt the need to speak up on this one but when you're a middle-aged white male you're not afforded the right to speak up on any of this without being IMMEDIATELY labeled a racist (hence the throwaway!).