I could be wrong, but I have a strong impression that Makerworld currently (manually?) checks new uploads before publishing them.
I don’t see any bulk uploads and verification takes an unusually long time.
Hopefully this isn’t just a test, but stays that way permanently.
In this case:
Thanks, @Makerworld!
I hope so, fingers crossed! 
Well, the wish was probably the father of the idea:
6 scam uploads in just 15 minutes, by a new user.
This leads me to suspect that instead of an upload control, there might have been a server problem or an update and no new registrations were accepted for a while, what stopped the scammers.
A pity …
Has anyone else noticed that there were hardly any downloads counted among all of the new uploads today?
[Update]
The 5th of 5 uploads I did in a single batch that took even longer than the other 4 failed, most likely due to a time-out as it was in the verifying queue for at least 20 minutes.
I deleted the entry and uploaded it again. It took less than 5 seconds to complete the review process this time.
I am almost certain there is no human in the mix currently.
If they switch to a human model, I imagine they will end up with a mix of human and trusted pass-throughs as trying to process each one would take even more staff than they can’t get for customer support problems. The trusted model would allow those with a proven record to get through entirely unless that trust is lost or lowered in the future.
[Original]
Reviews are taking longer.
I uploaded 5 models a while ago and each took much longer than normal, one is still in review.
This has happened before, previously due to a server slowdown.
They may have introduced manual reviewing processes, but, if history has anything to do with it, it is just an equipment issue.