A big question: does modern reception of antiquity primarily use Rome for historical settings and Greece for mythological ones? If yes, why? Has anyone written about this?

I've heard this suggested quite a few times for games, but I don't know whether anyone has actually counted them. I've got a spreadsheet for single protagonist games from Paizomen I have divided by h/m so could use to check those at least, but I've gone on holiday and left it - remind me next week!

This is purely anecdotal, but my sense is that people typically are more familiar with Greek mythology than Greek history, while they’re more familiar with Roman history than Roman mythology.

I think yes. I don’t know if anyone has officially written about it but I’ve heard the idea mentioned in Q&A sessions.