I do not generalise. For me, whether I like a mirror "selfie" depends very much on the subject and style.
Yours is [i]far [/i]better than most I have seen. It looks natural, not as if you are using the telephone to photograph yourself.
Many of them are pretty dire as portraits, the image dominated by the arm and 'phone, the background often the toilet presumably because there is no other mirror in the house.
You seem to have used a large, full-length mirror, and that helps. It let you stand back and hold the 'phone in a natural pose, as if using it to converse telephonically. (As I believe some indeed do!)
Otherwise it's better to take a self-photograph using a simple digital camera with timer on a tripod or other suitable mount. You can also use this method for outdoor photographs. It takes a fair bit of thinking about and care to frame the photograph, including test shots, but allows natural images. I am not sure if "smart"-'phones can give this facility even if you have some suitable mounting for the instrument.
Why do you need a mirror to take a selfie? Isn't that the whole point of taking a selfie in the first place, that you can put the camera in front of yourself and snap the picture like someone else would do if they were holding your camera?
