They are neither small nor particularly successful.
[1] https://www.forbes.com/sites/stevenli1/2020/02/17/stitch-fix...
Instead, I think that a post like this describes how they approach a challenge and how they automate work that would require manual annotation. I actually think of this analysis more as decision support (making manual review easier) as opposed to full-on automation.
1. It's a pretty common misconception that StitchFix is subscription only. A lot of their business is ad hoc just pay for a "fix".
2. Also, as far as I understand it, they are just as much a tech company as they are a retailer, if not more.
3. I know someone who works their, and from what they tell me StitchFix seems to really have their act together and just be well run in general.