> the Swedish are proactive about accommodating

If I had to pick out one thing Swedish culture does well, commercially, that many European cultures do not, it's allowing for dissent to be discussed [1]. Saying "I disagree with you" isn't an affront nor an insult, but the voicing of an opinion. That is not always true e.g. in France, Spain, Korea or the Middle East. (It's untrue in many American corporate cultures, too.)

This isn't a rule. But the number of Swedish teams where I've seen a junior productively question a senior in front of me is far higher than elsewhere in Europe.

[1] Switzerland, Ireland, the Netherlands and Denmark are also good at this.

I think what you've found is a reflection of the du-reform.[0] Swedish people are allowed, nay expected, to poke fun at their supervisors, as a show of good faith and encourage exactly that kind of bottom-up decision making that is so crucial to good teamwork.

[0] https://en.wikipedia.org/wiki/Du-reformen

I think the du-reform was a reflection of the underlying mentality.

That's a fair point, but perhaps splitting hairs to some extent. It is certainly both true that the du-reform was made possible because of the contemporary context, and that the du-reform became a clear signal from the higher-ups in society that this change was embraced.