I'm a programmer and what you'd probably call a computer nerd. I used Windows XP, Vista and 7 until 2016, when I then decided to give Linux (Mint+Cinnamon) a try. Loved it so much, my dual boot days were short and I quickly started using the penguin OS as my sole daily driver. After some very traditional distro hopping, I landed on Manjaro KDE, and have been a happy user for some years.
From an end-user PoV, Manjaro is great because of the frequent rolling-release package updates, nice community support and kernel and driver tools (the mhwd ones), while KDE Plasma is by far my favourite desktop environment, being simple by default but very powerful when needed. GNOME has a more Apple-y look to it, which I know is quite attractive as well, but since I'm more of a power user, KDE stuff is a no-brainer. Other DEs and tilling WMs are also nice, but I'm so happy with KDE I'm not going to switch anytime soon.