Exactly. It shouldn't be an investment vehicle, rent on land causes rocketing costs on everything down the chain. Only big monopolies survive. Places that are well governed and cheap to live in are often creative hubs.

You might want to argue that monopoly is efficient, but it's only a temporary thing until they have built their moat.

So who is going to spend millions on multi unit dwellings? Do you think everyone should be forced to buy a home as soon as they move out?

Tail wagging the dog. Land costs wouldn't be millions if you couldn't turn the thumbscrews on tenants.

To be a little less glib, it's easy to imagine other non-profit funding structures such as co-ops and government help (dirty phrase in the U.S. I know).

I imagine a lot of the costs of actually building would decrease a lot when remove the incentive for NIMBYish building codes.

There would be challenges as you point out, but the overall situation would be much better for all of society.

Yes because government housing has worked so well in the US and condo associations that are owner managed have such a good history.

Increasing inventory occurs by building more housing.

It wouldn't be linked to inflation, as the housing and renting market has historically been above inflation. So limiting to market rate would still be beyond inflation.

It would be balancing between having housing as a necessity vs a comodity.

“The market rate” is by definition set by people acting in their own self interest in a competitive market.