In principle, I can also imagine a "new" leasehold agreement that then runs for 80-90 years in theory. But I have to say, when we were searching and sometimes also saw a house where the contract still ran for about 25 years or less, that was more of a "hmm, no, I think rather not" for us. So, we didn't even inquire anymore about what usually happens at the end of a leasehold contract or what the specific regulations are (so yes, we absolutely exited there with prejudices, I plead guilty). But we are probably not the only ones there.
There have already been a few reports in the press here where, after the contract expired, the costs for the lease were significantly increased (which partly was because they were ridiculously low in the case of a 90-year-old contract—but if it is then increased tenfold, you might still not be fully prepared for that, even if you have a buffer in your household budget) and also some cases where the lease was specifically not renewed or should not be renewed because the grantor wanted to use the areas differently. I mean, to a certain extent, that is also simply the point. From a societal perspective, that certainly does not have to be wrong... I mean, the cities here were sometimes considering increasing the use of leasehold precisely to possibly allow discussions about repurposing again in many years if that then proves to be sensible, and also so that not all inner-city areas pass into private hands (and possibly have to be bought back expensively later). But for the individual who then has the house on the land at the expiry or near the expiry of the leasehold, it is of course a factor of uncertainty. What compensation payments will have to be made in the end, I actually did not know exactly. I have now taken that away as an insight for myself (and it certainly eases the problem for me).
Regarding the "investment backlog," I can also imagine that. My parents always put a lot into their house, but for 1-2 years now there has been discussion about whether a railway line should be laid there. Right now, a different route is under discussion again, but they still have it in the back of their minds. You then really think a third time about whether to put photovoltaic panels on the roof, even if realistically it will still take years until the issue of "railway buys up land" becomes serious. Measures around the house often only pay off economically after decades (ecologically, however, often much earlier), and I suspect that they will eventually simply no longer be carried out? This is similar to the person who a few pages ago said that in 10 years of renting out a house, they did less in the garden than in one year in their own house garden, even though they previously could have done it. So ultimately, it is of course individual, but I could also imagine that with a leasehold plot, some people will have certain mental blocks in the back of their minds. Especially if we no longer talk about a 90-year term, but about half or a quarter of that...