Why would you want a half-open interval when booking an AirBnB or flight? If I search for flights from February 24 to February 24 I don’t expect the empty interval.
However, as an AirBnB host, this bit me once because if you set that you're available on December 1, 2 and 3, guests can actually book December 1 - 4. But this is more because availability uses individual dates (almost like closed ranges) instead of half-open ranges like bookings do.
For booking flights, though, it's more like you're booking two individual flights on specific dates, it's not really a range at all, and so it doesn't really matter whether you think of it as open or closed. The flight search engine might want to check that the second flight departs after the first flight lands, but that has more to do with the flight times than the dates you enter.
The expectation depends on how you define "from" and "to" :-D
Since the HN community is quite mathematically-minded, I'd expect there all four possible kinds of definitions in the inner minds of HN members. :-D
I thought about it and this applies to an AirBnB, or more generally, a vacations, too. A vacation from Nov 25 to Nov 27 doesn't mean you stay from Nov 25 0:00 to Nov 27 23:59:59, but it means "arrive sometime Nov 25, leave sometime Nov 27" - a set of two dates
Once you swap to a higher precision format for an actual database search, you get all the messiness from the article.
We're squarely in the realm of preferences here. I'm the exact opposite of you: to me the last day is not included.