I have never had much success with a constant clean tape mask using a straight bit, it always lifts for some reason, fast speed, slow speed, in the middle same issue. 90degree v-bit gives me a solid reliable smooth edge on the mask.
As far as the painters tape. my point was for generalized masking (first few pictures where you blocked out an area for the silver). For detail carving through a mask, vinyl cannot be beaten IMO.
It’s all about the fun and experiments, you’ll find what works for you.