Street cred is not the rare clothes, that would be a sensible way to gage NPC reactions to the PC (and gate progression and stuff you van buy from shops and pretty much 99% of the stuff "levels" are doing) the rarity of each bit of clothes? waste of time given that shouldn't be a thing NPCs are aware of.Maybe not... If the Street Cred level is a variable for the fame, you could just compare this variable to another NPC status variable that would represent some type of affinity with a 'famous' V. Two numbers, one check.
In practice, e.g. if V is walking down a crowded street :
[Too low level Street Cred} : In appearance the player sees no reaction from the NPC, which means that V's level is too low (considered as a nobody). But that's a very common thing because in general many NPC just don't wanna interfere with other people's business, may they be famous or not.
[Required level Street Cred] : In appearance, some of them start looking differently at V, nothing too obvious ofc. They may seem interested just by how they look more intensely at V, like they would be open for discussion, or in contrary they can stiffen their jaw, making agressive eye contact or mumbling things when you get past them. And some potential "midnight chess partners" could make small body language in mark for their appreciation of your presence (look away blushing, play with their hair, whistle, etc.)
That detail within an immersive sim could serve as a whole social feature : if the players pay enough attention to that, they could have a clue to who may be a potential friend or rival, or other type of people that V could have substantial interaction with. Another good point would be to break that rule some times and make scammers looking friendly too, like if you follow them to a dark alley they'd try to rob or kill you.
And last, I think that it would serve the immersion if the same method could apply into the dialogues animation as well : most of people will look neutral, jaded, unfriendly or bored... but some of them must react to your reputation and look at you differently just so the experience feels more tangible.