/me goes to poke the release notes.
Oh my... 2015? And nothing since. Yikes.
Well another alternative that I occasionally poke is KolourPaint in KDE (included in my preferred window manager) https://kde.org/applications/graphics/org.kde.kolourpaint
I still much prefer Gimp... so rarely look at the lower demand/feature editors.
Pinta was heavily inspired by Paint.net but hasn't had an update in awhile: https://pinta-project.com/pintaproject/pinta/releases/1-6
KolourPaint is more like MS Paint: https://kde.org/applications/graphics/org.kde.kolourpaint
A website called AlternativeTo can be good in these situations: https://alternativeto.net/software/paintnet/?platform=linux Looks like it recommends a tool called LazPaint, but haven't used that one personally.