I realise this has been addressed in other threads, but I just wanted to add my voice to the mix in the hope that we may eventually get M1 support. However, I’m not holding my breath.
According to this Blizzard forum post by @Ruffus, Blizzard has knocked this into Apple’s court suggesting it’s an issue with macOS 11 Big Sur rather than Starcraft: Remastered. To Ruffus’s point, it does make you wonder how SC2 and WC3 are seemingly working just fine (under Rosetta, presumably).
I wonder if it’s too much to hope that one day we’ll get native M1 support for SC:R, SC2 and WC3 as we have with World of Warcraft. I suspect it is.