I remember that when Paint started being funky I found a Windows XP exe and used that. I want Paint to be the graphical equivalent of hexedit.
Now that I'm on Linux, I use jspaint.app.
I still use the Paint from Windows XP, running in Wine.
I would use kolourpaint but for whatever reason overlaid GUI elements like the selection box and brush cursors leave trails on the canvas.
Fun anecdote, paint.exe crashed the other day just as I was finishing up my drawing of the tower of Babel.
Windows 11 26H2 w/ MSPaint is 10.26100.1. It's just right.