Seems a bit over the top as far as workarounds go. What we'll probably end up doing is create specific "onMain" methods to use while we transition to async/await (once we drop iOS12 of course, since the Concurrency library causes iOS12 apps to crash)
It just seems like the DispatchQueue.main.async and @MainActor scenarios here just really wasn't thought through by the Swift team when they introduced actors.
I'm surprised it didn't break Combine as well (or maybe it did and we just haven't found out yet)