It's legit. I also recommend using obtainium app from fdroid, which can download apks from github, and other sources. It also checks if there are updates for installed apps.
It has pros and cons. You fully trust the developer and also most often Github. For a reasonable experience you need a Github account and Token to avoid a fast rate limit.
Also, F-Droid is a really simple application, which doesnt support a lot of things, reducing attack surface a lot.
I use Obtainium and get most apps from releases, some from F-Droid. I would say, if it isnt known, prefer F-Droid.