I’d answer this differently depending on when you ask. 10 years ago (random, but long enough number) I would have said an easy yes. Both GTK and QT would have been acceptable toolkits to use as the cross DE issues weren’t that many and bugs got fixed. Ask me a few years ago and I’d waver. It wasn’t clear how ecosystem friendly GTK4 would be, so I might have optimistically replied the same. But caveat it with a “maybe support both X11 and Wayland.” But ask me now and I’d say to earn the label *Linux native*, you would have to support a lot. GTK4 has proven to not play well with other DEs. The jump to Wayland has caused a fairly significant split in DEs (this year has greatly closed the gap with many showing great progress in supporting Wayland) which means some apps may not work on your DE of choice. And overall, I’d be hesitant to claim that any app is truly *Linux native* because installing an app no longer guarantees that it’ll just work and look and feel right. You’d need to have builds GTK4 & QT, and make sure that they work in both X11 and Wayland for the next few years. When I look for apps nowadays, I tend to append my DE and/or distribution to my search. I currently think it’s more truthful (on Linux) to say that an app is native to a DE instead of to Linux.

Note: I don’t think GTK4 is bad. One of the best parts of the Linux ecosystem is that we have a lot of great DEs that have gradually differentiated themselves by UX. GTK4 not playing well with others is in part due to how different GNOME’s UX is. The toolkit is meant to serve one DE paradigm now and that’s led to higher quality on that DE. The drawback to that diversification is that there is no easy way to support all DEs. Your toolkit drives what you support (unless you go out of your way to fix things that GTK4 isn’t fixing - which is why I put that bit about seeing how KDE issues would be addressed). The word “Linux”, now more than ever before, describes an ecosystem (or kernel) rather than an operating system.