Maybe not on Steam. But on Itch, at least, I'll be providing Windows 7 builds for Sable's Grimoire 2.
The devlog on the first Sable's Grimoire game was misleading. That line about Windows 7 and 8 no longer being supported was only supposed to be posted on Steam. I've now removed that line from the devlogs on Itch.
The problem is that Steam doesn't allow developers to provide separate versions of a game for different versions of Windows. The closest thing you can do is create a separate opt-in beta specifically for Windows 7, which is what I've done for the existing Sable's Grimoire games. Whereas on Itch, I can upload separate builds for separate versions of Windows and just name the downloads differently.
So yeah, Windows 7 will be supported on Itch. Maybe on Steam.
The Windows 7 version will lack one specific feature (image oversampling). Image oversampling is used to make the game look better at resolutions above 1080p. Other than that it should be exactly the same.