If that were ever true, people would chose to spend a higher percentage to get a nicer, bigger, or better located place.
Unlike many goods, there is practically no upper bound on what you can spend on housing. You can't buy a better phone for $3000, but you can continue to buy a better home up to $50 million (possibly more).
And yes, I'm against communism partly because of that. It's an awful ideology.
I am not a fan of all the choices the USSR made, but you are mischaracterizing a society under siege by the capitalist west.
> Demand for housing also remains heavy because Soviet rents, heavily subsidized by the Government, are very low. A modest two‐room apartment will en for 6 to 8 rubles ($8 to $11.30) a month, including some utilities. A four‐room apartment wil rent for 14 to 16 rubles ($18.20 to $22.30). Apartments in more modern buildings cost more because of additional services.
https://www.nytimes.com/1974/11/11/archives/in-soviet-ingenu...
Sure, that's just a guideline, but it's presumably based on what is (or once was) reasonable and possible to expect.
Also I'm not sure rental rates in a country currently actively being invaded and regularly bombed is a good example.
From "Tragedy & Hope" by Carrol Quigley
I think he meant non-subsidized rents.