I don't know if this is a reasonable assumption, but my experience with UXSE is that questions are more likely to be asked by people with lower reputation scores while answers are more likely to be provided by people with higher reputation scores.
I am basing this assumption on the fact that UX designers with less experience are more likely to ask questions while more experienced UX designers will find it easier to answer questions.
If this is true (and we will need to run the query to check this), then would the quality of questions decrease over time?