As a native English speaker, keen feels like a very 1950s TV word. Don't know if that's actually true but feels like that way. I expect you're more likely to hear like cool today are some more contemporary word.
I'm also a native English speaker, sounds perfectly normal & commonplace to me.
“It offers fewer words for the people directly around you, but more for belonging at a distance” - the further I get into this article the more it just seems like sampling bias as a narrative.
Still in common use in Britain as far as I know. A more local (Bristolian) word would be "keener" used to describe someone who puts lots of effort into a task to win praise.
Brits still use the word somewhat frequently, though I haven’t bumped into many of them in the last ten years.