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.
Void Linux for the arch and gentoo crowd. It's a system that can be assembled more cohesively.
Nix and Guix - the ideas they bring to the table are revolutionary. I prefer Guix due to its use of Scheme (guile). But Nix is more mature and has more packages.
I've used Debian for years but tried Void on a really low spec netbook and it's pretty nice. The install is pretty painless and not having systemd is an interesting change for me.