MJ remained relevant because the media talked about him nonstop, including casting the following decade as nothing more than a search for the next MJ.
I'd argue Bron will remain relevant for the same reason: the media will talk about him nonstop. They will spend years seeking the next Bron. The media will give Luka/Tatum/Giannis/etc the same obsessive coverage and quickly realize it doesn't keep the lights on like talking about Bron does. This is not me waxing poetic about how great Bron is btw. I'm simply saying the media has lived vicariously off him for decades and that shyt isn't gonna change when he retires.
Hell you already know the next stage of this will be SAS/Skip/etc type blowhards saying they miss Bron because he respected the game unlike [insert next generation player].