It's hard to offer context here without divulging IC info.
Let's just say that between what I'm assuming are more seasoned players (Mentors, higher ranking members of factions, perceived 'elites', and my own experience, the message for me is, "This entire archetype, which touts stealth as primary in the BGBB is actually better served in general by learning disguise."
Add on that ICly, with the exception of Judges and one single other incident, I can't recall ever having been intentionally killed or captured by a character that wasn't wearing a shroud (ballpark of fifteen to twenty times on killings).
Though the street sam archetype doesn't even include disguise as a recommended skill (stealth, in fact, is) , the vast majority of killers I've encountered use disguises to do their dirty work. That isn't to say that all killers are street sams, but even so, when disguise is so heavily used despite so many archetypes that don't even recommend it? At the very least, that seems to imply disguise is a primary skill.
I've use stealth extensively over the last year. Between what I see (In my relatively limited experience) as niche opportunities, and the amount of tech out there that simply beats stealth, its uses are limited from my point of view. Disguise is universally useful in an everyday sense, and for any -character- regardless of archetype.
I think it boils to down to a simple concept mechanically. Concealing your identity is preferable to concealing your presence a lot of the time. Why? The risk of being seen hiding your presence seems higher than the risk of being seen hiding your identity. Disguise doesn't require a contested skill check (to my knowledge). It's just there until it fails. There is no mechanical way to see through a disguise other than your own skill failing or you the player doing it poorly. There are contested stat checks to see a sneak. There are IC devices that see sneaks. It's far more fallible a skill than disguise for concealing yourself. It's far more expensive in terms of UE investment to yield consistent payoff. That last one alone makes it a support skill in my opinion, unless, like Sly (if I'm understanding correctly), you do nothing else.