I play on the easiest mode and that damn whole stealth chain of missions was awful. Hated every moment of it. Forget if you never put points into stealth, then it'd truly be impossible.
Like when you mind control, why do the other NPCs and turrets think they're enemies and start blasting their own homie who's just trying to run to a corner? Also sometimes the social popped up but I couldn't mind control, even as hidden.
Had to blast some NPCs multiple times during those quests just to get out of the chain cuz it was basically impossible do it undetected.
I think it really depends on the perks you have in stealth and related perks. Because I have quite a few (not maxed), and thought it was very doable. Although I was about lvl 50 during the ryujin quest.
I just turned level 25, so I did the whole chain as like early 20s, but those missions were the only reason I put a single point in stealth. Straight up sucked.