On the West there wouldn't be even a chance for this business: nginx would belong to employer by default.
By default but if you have enough leverage you can get all sorts of allowances from an employer. I always have any clause struck about the employer owning anything I produce outside of work for example.
(I don't necessarily consider this to be an example of significant leverage just common-sense.)
It's not a 'West' thing, it's a US/wannabe-US company thing. Also likely illegal in most EU countries, anyway.
I'm sure you can't name a single rule or law which is exploited in this case.
If I said "Britain has draconian libel laws" or "The US has absurd copyright laws" would I be wrong? Off the top of my head, I can't name a single rule or law that supports my claim, I only picked up a sense of that from reading the news. Likewise, I read articles like this and I get the impression that Russian IP laws are basically just tools for running extortion rackets... that's my simplistic layperson's take on the situation, but I don't really see any credible counter narrative in this thread.
On contrary with US IP non-hijacking rules we see in the Apple vs Nuvia case.