[qsymmachus]

No one is arguing that Airbnb is solely responsibly for rent increases. It's one of many contributing factors, including limited supply as you point out.

Contrary to your intuition on this question, Airbnb almost certainly a contributing factor to rent increases. There are studies on this: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3006832

[missedthecue]

According to the paper, this is what the researchers found -

"In a baseline OLS regression with no controls, we find that a 1% increase in Airbnb listings is associated with a 0.1% increase in rental rates and a 0.18% increase in house prices. Of course, these estimates should not be interpreted as causal and may instead be picking up spurious correlations"

I wouldn't be quick to call that "almost certain".

[ng12]

Limited supply is the disease, AirBnB is a symptom. AirBnB is popular in major cities exactly because real estate is so expensive.