It's not a scam, but by buying from there you are funding terrible treatment of workers, poor environmental practices and plagiarism and trademark fraud for the creatives and businesses who created most of the original designs.
Their prices are so cheap because they pay workers nothing, use poor quality and mostly plastic-based fabrics, don't have to follow the same rules around environmental protection, and rip off other people's designs. It also doesn't last, so all that pain and damage will go into something that you'll have to throw away in a short while.
This!
I find it strange when everyone is apparently more aware of the wider issues affecting society & the planet eg BLM, sustainability, countries struggling with covid but not enough vaccines etc it's still acceptable for someone to get paid peanuts, treated like crap in order to produce something you can wear for a few times.