You mean they stopped innovating? Modern S class type of a car is technically a very sophisticated robot with hundreds of sensors that only looks similar to a car from 1990s (metal, 4 wheels).

Would be nice if same happened to humans- u would look like a normal human but inside are magnitudes of innovation, edited genes, nano bots etc just how a modern car knows if you fall asleep, knows outdoor weather knows tire pressure, sees impact happen seconds in advance to move your seat and tighten your beld... none of it was in a car even in 2000 I think.

Similarly you can take a look at a modern smartphone, looks similar to say Nokia N97 from what 15 years ago ? But a modern phone has a dedicated AI hardware, does absolute miracles with pixel videon and photography in terms of recognition of objects, extrapolation etc, computationally equal to a server work station from 15 Years ago,again nothing wrong with it looking simular or even behaving similar, it's fundamentally a very different device.