It really just depends. Hormones, pigments, enzymes, aminos, silica, cleaning agents, ferments, microbes, and more all have their place in grow rooms. I think most people's use of specialty additives are similar to doing a rain dance and burning your money as a ritual.
For example, I do a UV-A supplemented tent for funsies. That tent always gets free pigments added into the solution, it helps the plants be more amenable to the harsh light.
For example, I like growing that stanky/dank/gas/no-denying what that is type flower, which usually means I supplement with sulfur additives because most lineups don't have enough to grow really gassy strains out.
Where folks lose me is when their nutrient line drops a new bottle of magic blah blah blah every two months, then next thing they know they have like five grand worth of advanced in their basement across 28 powders and 79 bottles. That is complete nonsense, you'd be better served literally buying macros and micros in single-source at that point.