For me it’s PeppermintOS.
I started my Linux adventure a few years ago, and haven’t owned a Windows PC since.
I currently use Arch on my main rig, and I wanted to install Linux on two old laptops that I found laying around in my house
I then remembered the first distro I ever used, which is PeppermintOS, and I was amazed at the latest updates they released.
They even have a mini ISO now to do a net-install with no bloat, with a Debian or Devuan base.
Sadly, I believe the founder passed away a few years ago, which is why I was really happy to see the continuation of this amazing project.
I’m not as familiar with music/audio production, but I’ve done a lot of 3D printing from a Linux system.
For slicing, you’re spoiled for choice. The only one I’m aware of that doesn’t at least try to support Linux is Formlabs; Slic3r, Cura, PrusaSlicer, even Simplify3D offer Linux versions.
For modeling, Blender runs well on Linux if you’re of that persuasion. For engineering CAD, pretty much the only first-class citizen is FreeCAD, which is powerful if a bit of a pain in the ass. You can also use OnShape because it’s browser-based, but they’re trying to be Solidworks especially in price. I have seen Fusion360 in Ubuntu’s Snap store, but haven’t tried to use it.
I run blender and cura, so it sounds like I’m covered there and that’s encouraging.