I think "obsolete" doesn't mean "extinct", but "not necessary anymore". Lamplighters are not necessary anymore. The kind of lamps that require one are obsolete and have usually been replaced by more modern lamps. But you can still hold on to an obsolete profession, item or technology out of nostalgia or tradition.

Really? I live in Wroclaw and cannot recall any non electric lamps. Would you care to elaborate?

Sure; Last year I visited the place, at the cathedral island the lamps are lighted every evening.[1] It's a great sight, the guy walks fast, so if you want to make a beautiful photo you have to be quick. [1] https://www.getyourguide.com/wroclaw-l2036/wroclaw-cathedral...

There's a photo of him on the Lamplighter Wikipedia page: https://en.wikipedia.org/wiki/Lamplighter