First Dairy-Identical Vegan Ice Cream Launches at 5k Stores
vegnews.com
vegnews.com
For ice cream in particular I actually prefer vegan versions and I know a lot of non vegans who buy it because it doesn't feel as heavy and fatty as dairy based ice creams.
I overall don't really think ice-cream is the space I would bother devoting my time to. I think plant based alternatives are doing pretty well there. Try something like the Ben and Jerry's vegan flavours and tell me you need a "vegan" dairy based one.
Not sure how much the protein matters, seems to me that a good replacement for butterfat would be a much bigger breakthrough. Butterfat is crucial to the texture and flavor of ice cream.