This also happens in Steam, it is known that Valve allows anything and everything but anime highschool games. https://www.makeuseof.com/malware-hiding-inside-steam-profile-pictures/
https://www.forbes.com/sites/daveywinder/2019/08/09/critical-steam-security-warn...
https://www.digitaltrends.com/gaming/steam-game-allegedly-mining-cryptocurrency/
while itch.io doesnt block every new malware or such, it does at least a better job than a billion dollar company. Valve only claims it blocks and has malware scanning software. However over the years Valve fail to block at least 200 dangerous malware since 2012, 50% of games are copys of other games, 80% stolen content and over 10 lawsuits by the government of different countrys.
While itch.io has nearly less problems and does a better job.