It's also an open world level with lots of space to explore, 2GB is pretty small for nex gen 3D games even for solo indie productions like this one.
Viewing post in Spell Slingers: Trick or Treat jam comments
Ok I'm mentioning it because I did my first jam in 3D in UE4 and once zipped was 320MB and after following this:
https://docs.unrealengine.com/4.26/en-US/TestingAndOptimization/PerformanceAndPr...
I reduced it to a 120 MB download.
It is UE4 tho and nowadays I only do 2D, but you might be able to do something to reduce it to reach the 1GB limit. Cause download builds are already ignored by people who only want to play in browser, the dropbox extra step will make even more people give up.