This is a bit difficult to explain, but I am a person who feels irritated by short forms such as "u" for "you", "r" for "are", "wanna" for "want to", and so on.
Maybe this is because I am 50 years old. Why should age matter? Well, the habit of using those short forms has become popular within the last 10 or 15 years, and perhaps I am at the age in which I cling to old ways!
When someone sends me a follower request with a lot of "u" and "i" (not capitalized), I think two things: (1) This person is influenced by popular Internet usage, which is dominated by young people, and perhaps this person does not know the situations in which native speakers feel such usage is appropriate. (2) This person doesn't know that such usage in an introduction message feels kind of disrespectful.
Why does it feel disrespectful? Well, that is the question we can work on in this discussion!
