There are some well-made and/or challenging games I've played in the jam so far that have 10 or less ratings so far as of this post. The ones I can think of are:
Unstable Gameble (/jam/gdevelop-big-game-jam-5/rate/2733330)
Forest Frenzy (/jam/gdevelop-big-game-jam-5/rate/2714820)
Dr Franciumstein's Incredible Escape (/jam/gdevelop-big-game-jam-5/rate/2728676)
Orca Island (/jam/gdevelop-big-game-jam-5/rate/2720833)
An Unstable Mind (/jam/gdevelop-big-game-jam-5/rate/2728603)