Shog9's answer to the SE meta question 50 question per month limit? appears to confirm that there is such a limit, but this ELU user appears to have asked more than 50 questions in the past week.
Did the limit never apply to ELU? Does it no longer apply to any sites, or what? I'm not necessarily taking against the specific user here - even if there is a limit, it's certainly not publicised. Ignorance of the law may be no excuse, but ELU isn't a courtroom.
Also - I don't know if it's connected to the (imho, excessive) number of questions, but I notice that if I view that user's questions, the display starts off by telling me there are 90. If I then look at any individual question and use my browser "back" button, the redisplayed list says there are only 42 questions (so I'm going to add the "bug" tag to my question).