I had a car that had non replaceable light bulbs in the rear blinkers, just a strip of led integrated deeply in the tail light assembly. Of course the blinker died. Replaced the whole assembly. (And replaced the whole car later). Apparently some enthusiasts do disassemble them and replace just the led strip, probably requiring soldering etc. This company had designed cars for about 120 years at that point but still seemed to commit easy mistakes...

This makes sense when you realize most ICE car makers get a substantial portion of their revenue from maintenance and replacement parts.