I am playing in survival mode, and I was trying to build a pen for my Hoglin, but I noticed that trying to break crimson fences with an iron axe did not speed up the breaking process, I also tried this with warped fences and they also did not go any faster. I tried to use it with trapdoors as well, they too did not speed up. I assume that this goes with all of their varients. I tried it with planks, but they actually sped up when I tried breaking them.