I think that due to the Windows prototype zip getting flagged by Windows Defender (maybe? Could be another anti-virus tool; it happens sometimes with Unity games). The file (at least the windows zip, it might be the whole page) was marked for some kind of review here on itch (I unfortunately have no notifications from itch about this; I assume it's a policy thing).
I did a rezip with another program (7zip instead of the Windows built-in), and that hasn't been flagged by Windows Defender; and a scan of the build folder also detected nothing (but I did see the flag on the version I zipped with the Windows built-in when I did a scan). I replaced the zip here (and the one on mega) with the newly zipped one.
I believe it's a false flag, and I'm hoping there'll be an additional scan or it'll sort itself out haha. If I'm notified and/or there's something I can do I'll get on it though.