The survey isn’t really asking the right question IMO since most of us would mark a VO2max workout as “Hard” or “Very Hard” but according to TR the response should be along the lines of:
Easy - yep, could do that in my sleep.
Moderate did OK but wasn’t pushed.
Hard struggled a bit
Very Hard should never have started it.
So if you want (positive) adaptations then the only responses are “Easy” or “Moderate”, everything else will lead to things being scaled back.