I exclusively use Linux and Windows; I see something like this and ... it's a disappointment.
I think what's "commendable" is cross-platform development, breaking out of walled gardens to support everyone.
I’d rather have teams start with high quality apps and branch out when it makes sense for them. Maybe it never will make sense for them and that’s okay!
And I use a ton of proprietary tools: SmartGit, Beyond Compare, DataGrip, Postman, Word/Excel, Sublime, Docker Desktop, Blender, Slack, Discord...
The only thing I can find that's Windows-only are the two tools that make up for the shortcomings of Windows shells: MSYS2 and ConEmu.
Seriously; cross-platform (or at least multi-platform) is the future. The frequent posting of Mac-exclusive apps seems to be more about Mac-snobs trying to brag about (and justify) their decision to rely on Macs.
As to strategy: If they want people to buy their app, and they're getting all of this great publicity, then "branching out" later will have missed an opportunity to market to Windows users. Heck, Windows users will likely be turned off by their heavy "Can a native Mac code editor really be that much better?" marketing message...
I know I won't be likely to try out their app ever. I mean, if I wanted to go with a well-supported, fast, and clean editor, I'd just use Sublime.
Nova seems to be specifically targeting the Mac-snob crowd as their main selling point, and I don't think that deserves the front page of HN.