Realistically, I'd be willing to bet the only old Mac games people are going to want to play are for classic Mac OS, in which case you already need to use a VM and have done for at least a decade.

I'm struggling to think of any games in OS X era where the Mac would be even close to the easiest or best place to play them.

I appreciate the notion that if you've bought the software you want to be able to keep using it for as long as possible, but we're talking about the niche-est of niches here.