The downside risks versus the short-term gains are too asymmetric.
Car rental - damage is very expensive, margins are tiny House rental - long term loans, short term lets that have proved very volatile in the pandemic. Office space rental - wework, again long term borrowing, short term rental.
The idea that we can endlessly slice and dice risk to get a "free" gain is rotting society.
Learn a skill. Create value. If everyone does this we live in a better society. We cannot all live off each other. Someone has to create value.