I buy bikes for a life time......then I replace them in 2-5 years.

OK, it really depends on the bike. I’ve averaged 2-3 years per frame for MTB, much longer for gravel/road, indefinitely for our townie/cruisers.

In the case of road/gravel, my tastes and goals have changed over time. But other than the expansion of gravel bikes over the past ten years, not much else really changes, IMO.

For mtb the bikes kept getting better. A lot better.