Hi @TurboQiimer,
Rarefation is normalization, subsampling is subsampling your data. They're not the same thing. I might use subsampling in a simulation, teaching, or i I need a representative subset. I don't typically look for representative subsets until I get closer to 1000+ samples, and typically here only for samples. I would not recommend it for most analyses without consideration of what the goal is.
Best,
Justine