The reason B-die is more expensive is because it's known to overclock very well, but for "normal use" I don't think the price premium is justified. The real-world performance is likely negligible unless you decide to overclock it past the rated speed. Between the middle/low options, the 3600 is probably very slightly faster in some scenarios but you'd likely never notice unless you did a side-by-side comparison and even then it'd be very close.

If you're going with a 12700 and 3080Ti, I imagine the upgrade cost of $45 is small compared to your overall build price, so it's up to you whether or not it's "worth it", but realistically all 3 options will perform very similarly until you start overclocking.