I'd prefer a well-designed (not necessarily pretty) cross-platform application. Not so much because I think the Linux version would be unsustainable, but becaus

I'd prefer a well-designed (not necessarily pretty) cross-platform application. Not so much because I think the Linux version would be unsustainable, but because I'm an OS polyglot. The Jetbrains editors are a good example of this. Cross-platform electron apps would also apply, but generally I'd prefer more native applications, just for performance reasons.