A plague tale innocence and requiem are both pretty short and absolutely wonderful (and heart wrenching).
Technobabylon (and other point and clicks from that dev) is great and short.
CloudPunk is another good short game (more like an interactive novel)
Donut County is good too. Kinda katamari vibes.
The rebooted Tomb Raider series from the late 2010s is also a lot of fun and each one can be completed in at least 20 hrs. I know that’s over your limit but they’re great.