you're taking up more than you need at the expense of others

A government that prohibits all that isnt needed has been tried - that included getting rid of all landlords. It resulted in 1/3 of all people being killed before a neighboring country invaded.

It was called the Khmer Rogue

Because guess what, at the end of the day you dont need to live and the government knows that. It is why "need" is an awful standard in any discussion

To have it as your main source of income you're gonna have to charge rent above when it costs you for mortgage and taxes.

And building apartments should pay you more than the cost of a mortgage and taxes

. What this does is it funnels money out of people who didn't have the upfront cash for a down payment for a loan to someone who was already well off enough to afford a loan if not afford the building outright.

No, it means people actually have a place to stay rather than not having a place to stay. Without the landlord the apartment complex wouldnt exist.

It also keeps the market price of living spaces artificially high because landlords, wanting to keep their properties valuable for making money, will keep places empty exclusively to artificially reduce supply whilst having an every increasing demand.

That does not happen.

Landlords reduce prices to reduce vacancy. Having one unit empty doesnt increase the combined rents of my other units by 1400 a month. It doesnt budge them by a penny.

Now are places empty? Sure. Not due to landlords artificially reducing supply. Those are generally single family homes which are empty due to some combination of death, foreign money laundering (particularly among the mainland Chinese) and homes needing renovation.

. I would also argue it hurts the economy as it is funnelling money from the poor, who would otherwise spend it on things like food, clothes, or some source of entertainment thereby stimulating the economy, to the pockets of a richer person who will likely leave it sit in a bank account which locks it off from the economy.

...please explain how buying beer is better than putting money in a bank which allows for cheaper mortgages. Because money doesnt "sit" in a bank, if you deposit 10k in the bank the bank then writes a 100k loan for a starter house (fractional reserve lending)