works well metaphorically with it getting unwinnable. clean concept

I like the idea of the game eventually becoming unwinnable. It comes across as a metaphor for the slippery slope that our planet has found itself on with regard to climate change and the pollution of the oceans. (That may or may not have been your intent, but it's a good thing regardless.)

Maybe add a score counter for every trash dodged or time alive timer. The overall message gets across as the trash starts to become unavoidable as time passes.