In recent years, the number of hobby microcontroller options has exploded exponentially. We went from a handful of (expensive) PIC and AVR boards to the Arduino family, the Teensy, Raspberry Pi line, Beaglebone, Particle family, the famous ESP8266, and endless other rather powerful and inexpensive consumer boards. What ties all of these together is for most projects, it doesn't truly matter which platform and board you pick. If you wanted to make a PID-controlled keggerator with an LCD display, you can use any one of these boards to the same effect. The only time it matters is when you need a very specific functionality such as web-connectivity, digital signal processing (DSP), or high-speed control.
With so many options, folks are able to pick on a variety of criteria such as cost, ease of use, online user base, pin count and more. For the folks who are just starting out or want a quick weekend project, the decision tends to be an Arduino or a Raspi. For folks with a little more experience or need an extra little something, they might go with a Teensy, Beaglebone Black, or an Edison. The thing to point out here is that folks will choose their boards based on THEIR needs. And as I mentioned above, nearly all platforms can do the tasks of the others for most projects.
So then why knock people for their choice in platforms? I see online frequently people ragging on others for using an Arduino or another beginner platform instead of their favorite microcontroller du jour. Who the hell cares? They took their time to 1) make something that has never existed 2) learn hardware that is new to them, and 3) then shared it with you and the rest of the world so the rest of us could learn and draw ideas from their project. Unless someone pops onto a help forum and asks for help with an issue or pointers, just keep your mouth (or keyboards) silent. Who cares if an ESP8266 has better power consumption than an Arduino Uno? The project plugs into a wall. Who cares if the Beaglebone Black runs faster than the Raspi? The project is controlling a toaster, not a formula one car.
Like someone's idea but think you can do it better with different hardware? Then do it! Document your project, code, the successes, and failures of the project so others can learn. It is really easy to play back-seat-driver from the safety of your comment box.