Hi there, I used to be a mod here, but have been extremely inactive and retired for the past few years due to life events.
What I can share is that when I used to be releasing stuff (in the Windows Phone era), most of my releases were modded by myself.
Occasionally, I would also test some of the releases by other members myself. Naturally, it is impossible for mods to test/scan all releases due to the sheer amount of manpower needed.
What I can suggest is:
1. Always scan/test everything you download (regardless of who uploaded it).
2. Download only from reputable users.
3. If you're still worried, the best way is to support the developers and get it from a legitimate source. Perhaps consider making use of trial periods and/or refund policies if you'd like to try the product before committing to a purchase.