It's not just them being nice, it's the law! As an employer you legally cannot deny a request for working part-time unless you have a halfway decent reason.

In my case I was able to start working 32 hours a week at my previous employer, even explicitly communicating that I was going to work (teaching CS in high school) on my day off. I initially requested 30 hours, for working 7.5 hours on the remaining days, but they figured they should set a company wide minimum of 32 hours for people in (more-or-less) managerial positions. If I had pushed it, they probably would have budged on that too.

It is the norm to work fewer hours in many sectors, especially if you're a government worker, but in tech it hasn't been my experience (as an expat in NL). If you don't have kids it seems to be 40+ hrs or nothing and requesting anything below full time is "unfair to other colleagues" or "signals a lack of commitment".

Not sure where you work then. As a (dutch) freelancer I worked at at least 10 companies where without exception 32hrs was possible. Developer jobs though.

But at my internship long time ago, as a mechanical engineer, it was also possible.

None of them offer fully remote jobs though.

I recently tried and got exactly this, wouldn't be fair for the others to have to work more to compensate for me, and they wanted some committed to working. I will keep trying, maybe is the moment to shame these companies back to see if they change their behaviour.

Not my experience in NL, having worked 4x9 at 3 companies for the past years, only some minor pushback easily set aside.

Might be different at Booking or fintech companies.

Also, some Dutch companies and jobs within the government let you work 4x9 hours