I think what they (poorly) meant was that there shouldn't be individuals/entities that own multiple houses, to give everyone/more people the chance to own homes. There is a serious housing shortage because a lot of people and companies buy multiple homes. Some use it as basically a form of money (notably the Chinese) and others use it as a form of income (Individuals/entities that own 10 or more affordable/family homes and rent it out. Airbnb was/is a huge contributer to this issue)

As a rule, people today cannot buy homes and rent is a major reason why. In most places rent is over 60% of the average paycheck. How are you supposed to afford a house? You won't even get accepted for a mortgage with the average paycheck. This issue has a lot of consequences, suchas the birthrate is falling at an exponential rate. It's barely at the replacement level, and in some places, below. And the trend is continuing.

unless you're living there or otherwise using the place, it shouldn't be 'your property'.