Construction costs are currently skyrocketing

Include civil servants - align pensions with the retirement level. A big step towards improvement.

The problem exists even without civil servants, as the pension fund already requires a large subsidy. And civil servants don’t necessarily have a better age structure either, most of them are close to retirement. The pension claims of civil servants are also a hidden debt mountain for the future. The problem is demographic in nature and cannot be solved by shifting people from one pot to another.

There is still a lot of water flowing down the creek

There is already the EU directive to renovate x% of the worst properties each year.

Include civil servants - align pensions with the retirement level. A big step towards improvement.

As already writes, the higher pensions are probably one of the main reasons why anyone still chooses this career path at all. So many aspects of daily work are simply no longer up to date and lead to frustration. Flexibility like a crowbar.
Pay is often significantly worse than in the private sector, if there are comparable roles. Where the pay is good, like with teachers, nobody wants the job anyway because the framework conditions are increasingly deteriorating.
If interest rates are low, tariff increases are argued against by citing low inflation. If inflation rises, there is no room for maneuver due to tight budgets. It is bad enough that the Federal Constitutional Court has already had to reprimand the legislature several times because the pay system is being manipulated to exhaustion.
No, I do not work in the public sector. But as soon as it comes to pension and health insurance issues, it is pretended that civil servants are draining the funds or that their (significantly lower gross) earnings would quickly fix the budget situation. This only serves to distract from other absolutely structural problems.

Civil servants have a completely different legal status, so you can't really compare them (content-wise). Financially, of course, you can.
Self-employed people are a different matter, both regarding health insurance and pension insurance. However, I see no way to implement that fairly (for pensions).

From my point of view, the only possibility is to dissolve the intergenerational contract. After that, a mandatory private pension with a government-guaranteed minimum benefit and optional top-up.
The state just has to pay full benefits for one generation, which it will only do once most of the baby boomers have mostly passed away. So in 30-40 years. The foundation has already been laid with a shrinking pension share and longer compulsory working hours.

And it goes against me to write this because I am actually rather left-wing. But from a very high-level perspective, it is not really social for the state to fully ensure that people not only live reasonably well in old age but also comfortably and decently.
It should guarantee a kind of basic foundation and maybe ensure that you don’t completely lose what you have invested in retirement provisions (up to a certain extent). But everything beyond that I actually see as a private matter or personal responsibility.

But from a very high bird’s-eye view, it is actually not social for the state to be fully responsible for ensuring that one can live not only reasonably well in old age but also comfortably and adequately. It should guarantee a kind of basic foundation and perhaps ensure that at least what one invests for retirement provision is not completely lost (to a certain extent). But everything beyond that I actually see as a private matter or personal responsibility.

But I’m allowed to give more than 1/3 of my income away for 45 years, right?

I would assume

Am I gladly allowed to hand over more than 1/3 of my income for 45 years?

why 1/3?
Pension insurance is 18.6% of the gross salary (employer + employee, the employer even formally pays on top, but one can assume that otherwise the employer would add it to the salary).

No idea how much that would be, but yes, for this, let’s call it basic pension, one would still be required to pay a share. However, that would also finance your pension (in the future) and not that of your grandpa and your father.

Let's assume it would be less, because the demographic problem no longer exists and this basic pension would also cover a smaller share. So e.g. 10% of the gross salary. Then it would be ensured that you have at least something more than the basic security.
Anything beyond that you could decide for yourself whether to give it to the state pension fund to increase your basic pension (similar to today) or whether to invest it differently or just spend it.

At the moment, your contributions today are simply consumed by today’s pensioners and the claims you receive are becoming less and less valuable. Exactly because of the generational contract. Yes, Nobbi either lied or had no idea.

And if necessary, the state just plays through intermediaries and pretends to act on EU directives that it itself helped to approve. Quite simple

There is already the EU requirement to renovate x% of the worst properties each year.

One more question – and if not? Not financially feasible? Will forced expropriation and demolition by the state then follow?