Did makerworld implement some kind of verification/captcha to confirm you are human? 
Maybe it helps again bots uploading stuff but i have like 50 tabs open when i’m exploring the new uploads page and open each design i like in a new tab …it’s annoying i need to confirm every few downloads i am human 
I haven’t seen that yet. Maybe Makerworld was having DDoS attacks in your IP block? Typically it seems things like that drive sites to go through Cloudflare.
I spend way too much time on MW and have never run into that.
More like prevent volume downloading bots.
Could it be a dns thing ? i found out my connection is using 1.1.1.1 as dns for ip4 protocol
