Google Fi data service slow on IOS14.7 eSIM

Recently updated to IOS14.7, and moved Google Fi, T-Mobile, to eSIM on my iPhone 12 Pro Max. The data speed grinds to a halt when I needed it outside of my house, when wifi is available. I ran a speed test with two bars LTE, and it ran basically to 0.04Mbps.

After reading some articles on the net, my guess is that the IOS14.7 is having some compatibility issues with T-Mobile's 5G service offering. Or else, Any idea?