That is definitely not always true, and I would say its only true in the minority of cases.

To make more money renting short term than long term you have to be in a very desirable location in a town/city with a lot of tourist traffic, and you have to keep your labor and energy costs down ruthlessly.

Most cleaning companies want $30 an hour. You need to pay $120 to do a turnover. Plus you need to buy many things and replace them regularly. And you need to pay for utilities.

Unless you can book for high prices, at least $250 a night and more like $399 a night on weekends in season, and keep the calendar pretty full, its not worth it.