Appreciate your answer!

There are millions of subscribers on subs like r/malefashionadvice that do exactly what you say in your second paragraph, most of them are those interested in fashion but can't concretely judge themselves as they haven't built their fashion sense yet.

I had no idea such a subreddit even existed. It sounds like /r/cantgetlaid to me, but clearly there is a market for (poor) advice and reading others’ stories, problems and complaints.

But: OP will be starting from zero. And even if he had 5.8 M lurkers, which he doesn’t, how many would sign up to his service, take pics of 100 items in their wardrobe and then be confident enough to receive good advice to pay for it?

I have no idea, but if almost 6 million souls want advice on Reddit, maybe there is indeed a potential market.

Not sure why you're so negative, nothing about that sub indicates they can't get laid or offer poor advice, sounds like you just think you're better than other people.