Why? If we pass a law dictating that chemical companies have to pay for cancer patients that developed the disease because of their use of those company's products, does the state cover the losses of the people who hold stock in those companies? No.
Landlords always say that they should be compensated for the risk of homeownership. If that's true, then some landlords need to lose money.
The system you purpose is not a loss some times, it is a system that can be abused all the time.
Who says landlords aren't losing money?
I am currently taking a loss. Two units are rent control at 600 per month, the third at 2300 hasn't paid in ten months with an eviction trial next week, I am in the last unit. I will be shutting down the property and using it as a single family home due to this loss. If you remove the incentive you remove housing or prices rise to cover the risk.
I see rent control as privatizing the cost of a social problem. You create restrictive zoning then say random landlords will subsidize people's rents. The single family home owners should share in the cost, and to a lesser degree, so should the renters who benefit.
Now you purpose an expansion on that same idea. Just remove zoning so housing can be built. Don't add more impediments like relocation fees and guaranteed housing in new construction for old residents and price controls. Then you will just have legacy units and luxury housing, an exacerbation of the current system.
You're putting landlords should lose money before there should be abundant and affordable housing. Landlords still lose money, these policies remove housing from the market, cause distortions, and lead to the luxury / affordable split.
Landlords always say that they should be compensated for the risk of homeownership. If that's true, then some landlords need to lose money.