They had your best interests at heart even if it might not have come across that way. I'm glad you figured that out back then and the relation didn't turn sour!
I personally haven't met many Russians, but many Romanians seem to share this trait as well
On the other hand I started to appreciate way more the way the English do it once I moved there for a while and worked closely with them - they tell you what's wrong, but really nuanced and careful as to not openly offend. But it takes a bit of practice and skill to understand what's actually being said, and once you have the skill and understanding, you can correct things without openly offending anybody.
> stay with them for a long weekend in Amsterdam.
I guess he got a firsthand experience of the famously steep and narrow Amsterdam staircases.
I couldn't figure out what was going on, because this tendency you describe was on full display right from the beginning. They invited us into their home then started giving us shit as soon as we walked in the front door. I thought they were just snobs and wanted to say fuck your stupid staircases and stroopwafel ain't shit (lying of course), but held my tongue because it wasn't my family. My wife on the other hand wasn't as restrained and gave it right back. Hearing Oom Rob laugh at her precision strikes made it all clear. We got along great after that and really had a fantastic time.
For what it's worth, I find Russians are expert at this as well.