By definition, a frigate like the USS Samuel B. Roberts lacks the bulk to suffer a mine strike and remain serviceable, while a tanker many times larger may survive a mine strike that misses the vitals of the ship. Different results might obtain in the open sea against anti-ship missiles. There the large tanker would be easy to target and the frigate much harder, with terminal defenses like the Phalanx auto cannon offering a fair chance of destroying an incoming missile.
I wasn’t advocating tanker conversions, but this exchange just reminded me of that book I read. Being a navy vet, I found it amusing that our ships were ducking for cover behind the tankers they were supposed to be protecting.