As a designer who uses Affinity on Linux (notably designed a zine for 404 Media using it and wrote about it): Portability is a major concern with stuff like this, and part of the reason people get so insanely crochety about Adobe not porting their apps to Linux.

Yes, if an app works for you, awesome, and it’s obviously ideal to use open stuff. But we live in a society and as good as PDFs are, you’re probably not going to get a print shop to install Scribus just because you want them to.

(Affinity, it should be noted, is free to use, but closed-source.)

Context if it helps: https://www.404media.co/the-weird-way-the-404-media-zine-was...