In Narnia? Go look at the actual vacancy rate.

Go read the public filings from the big real estate companies in Germany - Vonovia, LEG and TAG: https://irpages2.eqs.com/download/companies/legimmobilien/An...

https://report.vonovia.de/2022/q4/app/uploads/Vonovia-SE_Ges...

https://www.tag-ag.com/fileadmin/content/geschaeftsberichte/...

There is no single company that dominates a city or market enough to “profit from keeping rental units vacant at scale”. Vacancy rates and driving them down is a massive talking point in investor calls. High vacancy is bad because investors mainly care about rental income. The aforementioned companies achieve 3% or so organic rent growth - which is LOWER than inflation.

You have very little understanding of how the business world works and I’d recommend to take a couple of courses or classes in that field. It’s the same suggestion you would give an MBA type posting his opinion about programming or ML on Hacker News I suppose.

There are strategic investors though that buy run down buildings without any intention of renting them out ever but holding them for speculation. This is wrong and harms society. Land zoned for urbanisation is a right that is granted by society and has implicit value only from society granting these rights. Speculations on these artificially (by said society) limited building permissions needs to be eliminated. The space does not have much “inherent value” in itself (e.g., assuming no building for the ease of argument) - but only gains value by being artificially limited in quantity by society.