From airline's standpoint it's logical - as some states and countries lift the lockdown order the flights might actually take place on normal schedule. From traveler's standpoint it's also rational - I get a full refund if United cancels the flight, but "store credit" if I cancel the trip on my own. I also get the same United voucher whether I cancel the trip a month in advance or 48 hours in advance.
This affects any lodging reservation in a negative way, though - what looks like a steady supply of bookings months out turns into a series of cancellations closer to the dates of the stay.
An insightful comment, and it's exactly why I booked a vacation flight for late this year already. United in particular was offering very generous terms - they were offering book now, and no penalties or fees for changing the flight within the next 2 years.
The answer to that question has been a definite "no" for lots of people during this latest and recent first wave (which has now started retreating a little) and I suspect lots of people will think twice before vacationing in a different country (even if that second country it's also in the Schengen area).
Even if I went along with the panic, it would take probably three months to go through with any transaction that would throw a desirable property onto the market. The demand is still so strong that the low price would likely chum the waters and competitive bidding would drive the price up.
I think these Airbnb liquidation sale headlines are being sensational and end up wasting buyers time.