Whereas one knows that relevant jobs are very poorly paid.
Your statement is so typical for those who are on the winning side when it comes to wage distribution. And if there weren’t people who also do less well-paid jobs, it would look very bleak in the country and you probably wouldn’t be able to simply live in or have built your house.
I have also done quite a lot for that. As a foreigner, I worked my way up from secondary school to the Abitur. Afterwards, I completed an apprenticeship and started studying. While I only finished my studies in my early 30s and additionally had to pay off xx,000 € in student loans because I paid for my studies and living expenses 100% myself, others have already been working for over 10 years.
And yes, anyone could do that. But many want to start working right after school, which is completely okay. Many are satisfied with what they have, even if it is not enough for a house, which is also totally fine.
Craftsmen earn less but can get many things done through connections (Vitamin B). For example, I know from my circle of acquaintances: while the mason worked on the house for a friend's electrician, the electrician installed the wiring for the mason, and so on.
And what are relevant jobs for you? My wife is a teacher E12 with over 10 years of professional experience. She earns more than 5,000 € gross. For me, that is a very relevant job. Nurses, another very relevant profession, now also earn very well (I know this firsthand because I work in a hospital). The only big disadvantage is shift and weekend work.
I think that due to the lower supply, craftsmen’s wages are also shooting up. Unless the owner keeps everything for himself...