Everybody keeps referring just to airbnb. All online rental platforms are an issue.
I have booked several rooms in Spain, and numerous apartments here in Germany on Booking. whilst on my walk from home.
One German example (from April ).
The apartment owner lives in the building, it's six apartments. Since purchase, she's been gradually renovating it over the past seven years (it was originally very run down). She renovated an Apartment and quickly realised that she can make significantly more money renting it out short-term than long-term. Even with only a 50% occupancy rate in her first year ( her figure) after fees, cleaning etc (tax deductible) she made nearly double what she gets from the apartments she has rented out long-term. So she eventually did the same with her other two available apartments.
That means that just 50% of the building is occupied by locals, the rest is visitors like ourselves.
I'm sure that the situation is similar elsewhere.
Spain: Sigüeiro is a good example: I rented a private room at the Albergue, it's actually in a separate building. An apartment with four bedrooms, two bathrooms, lounge and kitchen - it's now solely 'visitors'.
My understanding is that
@Molly Cassidy is completely correct, the idea is to make it unprofitable for landlords to solely rent on airbnb and to return these properties to the market. If it's uneconomical for the landlords to rent them out, then they will sell them. Either way they're returned to the 'pool'.
People that wish to simply rent out their properties short term whilst they themselves are away are unaffected. Eg:
I rented an apartment in Trondheim from a student whilst he was on holiday July 2022. My 10 days paid for his Month! Win - win.