Construction financing - How will it change in the future?

26-28 to the office with A 13.

right, I also said late 20s. However, I cannot pay off a house in 15-20 years on A 13/14/15. That's what I meant. Those are false expectations.

earn or be able to afford

Very true. But that was not the point. It was pointed out here that someone has too little equity. However, there can be many different reasons for that and it should not be judged immediately.

There can be many different reasons for this, and one should not judge it immediately.

Without significant / with too little equity, one should not build anything owner-occupied. No one is judged for that. Either I want to have something of my own someday and finance it solidly based on a solid equity base – or not.

It was never said that everyone can do it, only some. Besides, there is still a lot of land in Germany outside of Munich, Frankfurt and co. and not everyone has a birthright to a new building. Existing properties are often significantly cheaper, also because you usually do more yourself there.

Without significant / with too little equity, you shouldn't build anything owner-occupied

Ok, that's your opinion, I understand.
Wiesel has it:

Here, however, many want everything immediately and right now and when you think about an apartment/house at 30 or 35 and have no equity, the rude awakening comes and suddenly everything is unfair.
I currently have that in my circle of colleagues as well. Mid-30s, A9 and A13 and 0€ equity because everything has been consumed, and now they want 550,000€ from the bank for a house and start sweating with the repayment

or ridiculed, you could also say. But I find that unfair.

Without significant / with too little equity, you shouldn't build anything owner-occupied

and what am I supposed to do then with my family?? Renting apartments over 100m² (which is not exaggerated for a family of four, I think) is often just as expensive as the installment for the loan.

is often just as expensive as the installment on the loan

Sure, when looked at in a simplistic way like that, it does come across like that.
With your warm rent, you pay your landlord a whole bunch of additional costs, which as an owner of a detached house you would first have to cover and set aside yourself; of course, those are not included in your debt service. Besides that, the landlord pays for maintenance and repairs from your cold rent; those, of course, come on top of your loan installment.
And just from the costs that your construction financing does not cover (furnishing, kitchen...) you can nicely stay in renting for a few more years.

(Furnishing, kitchen...)

I often also need the kitchen in rent and furnishing anyway.

Milchmädchen-mäßig

Well, I don't know how the prices are in your region, but here we've now reached about €10/m² cold rent. That makes €1,200 for 120 m². I can easily manage the installment for a house with 120 m² as well. Then utilities (yes, definitely more for a single-family house than for an apartment) come on top. But I don't find that so simplistic. Especially since with a single-family house I then own property.