How quickly should one pay off a house?

Here it is presented as if it could be offset against all types of income, is that correct?

Basically, you can offset losses from V+V against other income. There are special features or restrictions for private V-profits and income from capital assets. But it can be offset without problems with income as an employee: 10d Income Tax Act

By the way, a not insignificant factor in the calculation is whether children are involved and whether you plan to leave something to them... or not. It is not uncommon for today's generation of retirees to say "My children don't inherit anything, I blow everything down to the last cent..."

I certainly do not claim to have paid off the house here in 10 or 15 years, by foregoing any luxury and living exclusively on tap water and dry bread. But I will certainly not leave my children a ruin that I have not paid off at the tender age of 70 or 75, let alone set aside reserves for renovations.

That is why it was clear from the outset that we would rather forgo unnecessary frills and not push all the controls to the max when it comes to the loan...

But I certainly will not leave my children a ruin that I have not paid off at the tender age of 70 or 75, let alone built up reserves for renovations.

Why not? If you have had a really good time during your life because of it, even the children might be happy, because they have probably benefited from it throughout their lives. And a half-paid-off property mostly still consists of a nice piece of land after a demolition.

Note 1: Invest €2000 per month in retirement provision (among other things, paying off the house, ETFs, and co).
Note 2: Invest €1000 per month in retirement provision (among other things, paying off the house, ETFs, and co) and €1000 per month in quality of life.
Note 3: Invest €2000 per month in quality of life.

How can one buy or invest in quality of life for an additional €1,000 or €2,000? We have a very large, centrally located house, two cars (okay, could be upgraded), fly on vacation twice a year, basically do something every free day or meet with friends or family.

Reducing work is also not sensible. My wife is already working part-time and I have only 38 hours and 3 days per week working from home – and while working from home you don’t really work continuously, but instead do household chores in between and do the weekly shopping during lunch breaks. I am already in such a position that I have my own issues – they don’t become less by reducing working hours – the work time is just condensed.

How can you buy or invest in additional quality of life for 1,000 or 2,000 euros?

We have already discussed that. But your question now also has nothing to do with the thread title! Just because one (or two) here think you can buy quality of life, it can probably be read from the thread that time for other things or ideals (for which you might have to “buy yourself free”) is rather seen as the goal. You don't have to follow the forum. If you (42) don’t recognize it, then so be it. If you find it meaningful to pay off the house, then so be it. You can also secure your children by setting up an account for them. You can also be selfless and donate.

Invest 1,000 euros or 2,000 euros more per month in quality of life. But how do you do that? How are you supposed to "buy" quality of life?

This question confused me a lot. My life consists of ideas that I want to try out. For that, I either need money or time.
So I take the 1k-2k for what costs money. Or I give up 1k-2k and in return get more time, which I immediately invest in new projects.

Sure, the things that would require a lot of money AND time are out of the question. I just do other things; I have too many ideas for one lifetime anyway.

We don’t have children and don’t intend to take anything with us to the grave in the end.