They will not be thrown in the dumpster, but that's actually a bad thing for NVIDIA. We had a very short period when lots of miners dumped their RTX cards on ebay and the prices fell a lot for some time. (then AI on RTX became a thing at small scales) When the A100/H100s get replaced, they will flood the market. There's many millions of $ stuck in those assets right now and in a few years they will dominate research and top end of hobbies. Only high profile companies/universities/researchers will look at buying anything newer. Maybe NVIDIA can do 2 generations of those cards, but ASIC-based solutions will hit the market and the generic CUDA will become a problem rather than a blessing. Same story as BTC miners and graphics cards.

Sure, they didn't get lucky with the tech they had to offer - that was well developed for years. They just got lucky that the next big thing was compute-based. If the next thing is memory/storage-based, they're screwed and the compute market is saturated for years - they have only gamers left.