Actually, the chances of building now are not bad at all, especially if you have equity and don't have to finance everything.
With individual contracting combined with personal contribution, I would build myself in BW for under 200k.
You also have to consider that those who have a house built must pay VAT. With construction costs over 400,000 euros, around 80,000 VAT is included. This money is gone and is not used in construction.
Of course, you have to design your building style with cost savings in mind. You don't necessarily have to make big compromises, but what is expensive simply has to be canceled. You can also be modest and upgrade properly later, depending on your income situation.
Today, however, everything has to be the best right away and immediately. There is definitely a certain mentality to be observed here.
Why should one go from a very good income situation into an uncertain future with exorbitantly high debt, in a geostrategically certainly uniquely insecure situation? We are practically on the eve of a major war in Europe, in which Germany will certainly be involved. Especially in BW, the automotive industry is facing a turning point.
In the current situation, I would keep my powder dry. Possibly, one really has to seek salvation elsewhere.
Reduce: yes, that's what we are currently doing to the extent that the result barely fits.
General situation: true. I also think about that. At the same time: what are the alternatives? Rents will rise in the coming years. If the economy continues, housing will be scarce. If I build in my life, then now; later we'll be too old. The house makes sense now, where we will have to settle down anyway for 15-20 years with small children.
The risk that the region will economically collapse is the relevant one in my view. That is a risk we would have to take if we build. We take this into account by ensuring the loan is not stretched to the limit, so we can absorb reductions / job changes / ... If things go really badly and we have to sell in a low market and move away, 200k - 300k euros are lost; then you have to decide whether the outcome is worth the risk.
Regarding other risks (war, climate, ...), the question is whether you want to approach things pessimistically / with a safety-first mindset and thereby miss opportunities, or be optimistic, with the chance to shape your life now while accepting the risk of having little left before retirement.
There are better times to build, but for us the decision has to be made now. We are not decided yet. Controllable building costs would help, making the whole thing manageable.