I have ADHD. I've always found Windows 7+ boring, which is interesting as someone in the IT field. I first got interested in computers at a very young age. Potty training age. Any free time I've had, I'd always spend it on a computer. Homework, not getting done if there's a computer nearby. Learning, gaming, more learning, I always found it extremely interesting.
My first introduction to Linux was when I was in Middle School. I hated it. "How do I install software? I can't just download it?" "Why can't I just put a disk in and just use it?" (Things have come a long way!). I didn't get serious about it until I tried running a web server in 2012 using Windows Server 2003. I learned very quickly the importance of keeping an OS up to date. It was then that I remembered that there was this completely free operating system that gets updated regularly, so I decided to give it another try. I used Ubuntu, so it made sense to me to try Ubuntu Server. I started to appreciate apt and package managers as a more secure way to download software from trusted sources. There were plenty of guides on software like LAMP. Plenty of neat catches that take up time, but are invaluable to learn. You got closer to the software and the hardware with every step, and really begin to learn how computers work. You can play with security settings, and it's not just going through a boring list of GPOs, there's text files everywhere that you can edit and see what change they make. It's all interesting. The things that annoyed me before, have become interesting "Oh, things don't mount instantly because there wasn't a service that did it, but it can be done with a line of text on a console", and don't get me started on the console. Once commands get into my long term memory, I really start to fly around the OS. People have even commented "I don't know how you remember all these commands" and it's an amazing feeling. Any given day, I can scroll through man pages, new software, do experiments, and help other people who have trouble with it, and really enjoy doing it. At my job, I'm known as the "Linux guy" and it's a title I can easily live with. It's a skill that takes years to hone, but I never found it to be work, it was always something I did in my spare time because of the excitement of getting my hands dirty.
While the OS was probably never designed with ADHD in mind, it all came about with how it was written. Every new iteration of Unix to Linux has added, and removed functionality in small parts. Open source developers add small bits of code here, and there, Unix developers all had different ideas in mind and added their small contribution to the source, which all ended up creating a hodgepodge of entropy, and that is what makes it special. People that don't have ADHD can't get their heads around the OS that has 15 different ways to accomplish your task. Sometimes you want to do it the easy way, and sometimes you want to do it the hard way to learn. It has both permissions, ACLs, and SELinux that can cause issues. They don't understand why one line of code can trash your entire setup, and doesn't even ask you "Are you sure you want to chmod -R 600 /?" The OS doesn't ask you because it trusts you. When you write a script that installs all your patches and builds your software and it all comes together, it's satisfying and affirming. Linux doesn't scold you when you mess up, it lets you come to conclusions as to why something went wrong, it's patient.
When people don't understand me, Linux does. Long live NIX!