That only works with the Attack action. So you can't do that between Flurry of Blows attacks.
You haven't been counting it for the Monk either, so fair is fair. Plus Fighters actually have ways of improving their chances of those attacks still hitting.
Fighter can reroll it too with Indomitable (lousy as the 2014 version of it was).
That ability doesn't even work in a lot of cases because to take that action, you have to be in control of your characters' actions. And a lot of Fear and Charm effects take control of your characters' actions away.
Within a ranged weapon's normal range why would I be attacking with disadvantage?
Better than going against CON saves.
4*(1d10+5) = 42. Over two rounds that's 84.
At the cost of double the ki. For only 13 points more. If I'm going to be spending ki at double the rate, I'd better get a lot more than just a 13 net gain.
Which will never meaningfully happen against something with Legendary Resistance. By the time you mulched through all that boss' auto-saves, it was likely going to die from something or someone else that round anyway.
Wait, we're talking about Wholeness of Body here. Do you even pay attention to your own argument?
Concluding stuff based on experience has no value. Because everyone's experience is different. What were you fighting in each of those encounters? What was the encounter design? Who else was in the party? Etc., etc.
All you have is anecdotal evidence, and that will never fly. Because if that's all you have to go by it's always your word against theirs.
Clearly you do not know much, then, because they absolutely are the weakest in 2014.
Tell me, are you going to claim the 2014 Monk is better than the 2024 Monk?