I didn't ask why you wouldn't bring it up, I asked why you would be embarrassed. I would similarly ask why someone else would ask. My assertion being that nobody cares what anyone else's phone is. I'd assume if you bring up your phone, it is something you want to talk about, so I'd let you. I might even be interested in your interests in your phone. Ahead of time, though, I flat don't care.
There are countless choices you can make in life that nobody else cares about. What brand of shoe are you wearing? What style? What brand of shirt? What style of cuff? Collar? Buttons? Do you wear pins with your outfit?
I don't even think my points here are interesting. You shouldn't let yourself be influenced by what others care about in things that don't matter. More, I don't think my points here are counter to your declared preferences. I agree that it is strange to care about someone doing something slightly different. I'm not the one that said I'm embarrassed when I do, though?
Edit: Also wanted to say that "this" got shifted some there. The sentence I had in the last saying people that bring this up are not serious on it, is on people that bring up wanting a cheap phone. It is not necessarily a bad unseriousness. But it is unserious. Nothing is stopping you from getting a cheap phone today.