Nice , first I heard of that but good tip.Finally solved the problem ... The new scam text blocking feature on Pixel phones from Google blocks the short message codes from T-Mobile from verifying your phone number during final RCS set-up. T-Mobile called me back and provided me the following short codes for turning off scam blocking.
#634# dial - Turn off Scam ID
#632# dial - Turn off Scam Block
My phone number instantly connected once I entered these codes.
Remember to turn back on the scam blocking once you have RCS on with the following codes.
#664# Turn on Scam ID
#662# Turn on Scam Block