The problem is that a lot of people dont want to or cant own homes because they dont make enough.

Not true. They can't obtain a loan because they don't have the prerequisite capital for a downpayment, because they're already paying someone else's mortgage and aren't saving that money to buy their own. Market rate for rent is higher than the market rate for mortgage payments on the same property, because landlords pass on the cost of financing to their tenants so they can still make a profit.

For those who don't want a home, they can still 'rent' from coop housing or land trusts or municipal housing. Landlords are not necessary even for those who arbitrarily don't 'want' to own a home.

A credit union is not a “community union”

apologies for the confusion. credit unions are typically community owned, but you're right - they're not called community unions.

credit union and is just the same thing as a bank

kinda, but the important difference is that the patrons are voting members for the management of funds and distribute profits democratically. Equity stays within the community and is better than a private bank that siphons wealth for private benefit. In the case of mortgage lending, if a homeowner defaults, the community (e.g. the credit union) takes possession of the asset and can resell or lease it to a new community member. The asset is still democratically managed and isn't subject to an outside private investor.

For every private institution that enables private ownership, there is a publicly managed counterpart that is more democratic. Private landlords are simply not necessary.