It is unfortunately pretty standard, most antivirus is going to err on the side of caution with mysterious files like the ones we download here. It’s one of the reasons having a web playable version is so encouraged with jam games.
Malicious files are rare but they do happen so there’s no guarantees unfortunately. You can usually get an idea by looking at the dev’s profile or comments on their games to make sure they’re legit, but even that’s not much use if they’ve been hacked.
Just be careful, and if something looks dodgy or you’re generally in doubt, don’t risk it.