Interesting, but with a big catch. From what I see in the signatures here, a lot of people would have to upgrade there systems by a lot in order to play at a decent resolution and with all the details FS2020 is offering, you would not be able to play offline, unless you have a squizillion TB of space, you need the most juicy internet connection, and so on, and so forth.
So - While i like the idea, I guess i would set off almost as much customers as a subscribtion. I think DCS should be DCS, MSFS2020 should be MSFS2020.