bwells2 i did install Carrion off F-Droid to solve the insanely high uptick in spam/scam calls
I could be wrong, but I think the reason your getting more spam calls is because Apple and Google can 'screen' the call and the phone won't ring if they detect its spam. GrapheneOS doesn't do that so all calls come through. A good thing, in my opinion. I don't want Apple and Google screening my calls.
As for texts, de0u made a good point. Its either iMessage or Google RCS interfering most likely.