GPUs age surprisingly gracefully. If a GPU isn't cutting edge, you just tie two or more of them together for a bit more power consumption to get more or less the same result as the next generation GPU.

if there's ever a glut in GPUs that formula might change but it sure hasn't happened yet. Also, people deeply underestimate how long it would take a competing technology to displace them. It took GPUs nearly a decade and the fortunate occurrence of the AI boom to displace CPUs in the first place despite bountiful evidence in HPC that they were already a big deal.