I think it is interesting that you find the name to be what is confusing when it having a name is what allows it to be clearly defined as a game term.
Maybe I am just more used to the idea of some things being game terms (their definition is determined by the game, not the usage of that word outside the game) and some things being just words, and have an easier time telling which is which because of it.
Yeah, that's a really good point. I guess when 5e tried to move towards more "natural language" they wound up with a few terms that are in this gray area. Like, it's easy to explain what a "turn" and "action" are, but "bonus-action" requires a next-level rules-comprehension that many players just aren't very interested in attaining.
I think people who discuss rules on-line (e.g., us) are more likely to read them and digest them ahead of time and notice the interactions and limitations. But I think most people who sit down to player D&D just want to play and don't want to put much effort into understanding something like the action economy or bonus actions or how the "Ready" action actually works.