Indian tribes, like AC- or non-NV focused casino operators, absolutely want legalized sports betting, since their properties are concentrated outside of the one market where it's legal (NV). I doubt the table games and slots would be hurt by that, would make the pie bigger.
If they had their druthers, they'd probably not want the online market fully blessed and regulated though, better to get people in the house since they have the properties, but would I'd think accept it on or offline at the end of the day.