I Don't know about France but in some places its near impossible to evict squatters, meaning if your property stands empty a month (e.g. waiting for new tenant or repairs) and some squatters move in you are basically screwed for years to come - they won't pay rent, you'll lose thousands and much lifetime evicting them, and for a few years they'll run down your property as they have no legal or other interest in maintaining it, so you are out huge amounts of money.
This can happen to the slumlord (who will then send someone to beat up the squatters), to the big capitalist (who will go through the courts and win) and to smalltime owners where that is maybe their family home or future retirement apartment (who will suffer the most).
Homelessness/lack of housing is a problem, but squatting is in most cases not the right solution.
But if someone just moves into your property why can’t police just kick them out? That’s an illegal action. If someone came into your house and started stealing your things and you call the cops on them you don’t go to court to prove those things are really yours.
Because in many locations around the world, it's not as simple as a criminal offence, it's a civil dispute, as once you have commenced "squatting", you are now an occupant, rather than a clear trespasser. Many squatters find squatting manuals online detailing the local laws and how best to approach it to maximum time available in the property.
In France once someone entered your house (and stayed a generally agreed upon 48 hours) you have no right to evict them.
Then starts a possibly very long process to have them evicted/ If they have a child you are basically screwed and won't be able to get your property back. Or you will wait months/years and get a ruin back.
This can happen to the slumlord (who will then send someone to beat up the squatters), to the big capitalist (who will go through the courts and win) and to smalltime owners where that is maybe their family home or future retirement apartment (who will suffer the most).
Homelessness/lack of housing is a problem, but squatting is in most cases not the right solution.