e why are those civil servants not up to speed on current laws and why does that go so far, as you suggest, as wrong info being on their govt's website?
It's simply not a priority for them. Websites, government or not, are not official channels of information here.
I had thought if there were regulations and they are published on a website with a Polish government URL that I could depend on them? But apparently not?!? Visa rules have changed and are out of date but no one's updated the website? Is that what's happened?
That's exactly what's happened. Normal here in PL.
As you probably know, in the UK it's not unheard of for people to get hold of empty flat keys and pretend to be landlords and then steal your deposit, happened to 2 people I've heard of, one of them I know personally. Never saw their money again.
Here people are far less trusting - they often want to see all the documents etc. The best way to find somewhere to rent is either through Gumtree or ideally by asking around. Best to avoid professional renters with several flats to let and stick to people who are renting just the one.