Dutch programmers probably have little incentive to get it right, because Dutch makes relatively light use of accents. I wouldn't be surprised if Czech programmers, for example, were much more meticulous at converting between UTF-8 and legacy encodings.

Here in CJK territory, using the wrong encoding makes the output so obviously broken [1] that mistakes are almost always caught before hitting production.

[1] https://en.wikipedia.org/wiki/Mojibake