Depends on your definition of "fizzle out". If you mean "not dominate the future, but be relegated to merely a niche tech", then:
Ruby on Rails. Modula-2. Every JavaScript framework since ever. Supersonic passenger flight. Space tourism. Emitter-coupled logic. Gallium arsenide (still has my vote for a name for a speed-metal band). Musk's Boring Company. I'm sure I could go on with some more thought.
I didn't understand the comment to be about specific products, but more overall categories. I think space tourism is likely going to be a huge category, it's just decades away still. I don't know about supersonic passenger flight or building tunnels everywhere. It may never be worth it for those categories.
But regardless, I don't think that many people really thought Musk was going to build much with Boring. I certainly didn't.
And has anyone in the last three decades (other than Boom's hapless investors) thought that supersonic passenger flight was going to be huge?
Not really...crypto is the biggest one that people cite, but the crypto ecosystem seems to be humming along. It hasn't taken over the world, but it also hasn't really fizzled imo. I haven't really paid attention to whether VCs are still investing there.
I guess maybe VR is another one? But that's another example of a slowly growing ecosystem.
I think mostly the people who think some piece of hot tech is going to take over the world aren't usually wrong, they're just early.
Hmm...I didn't understand the comment to be about specific products, so I'd take Glass and Betamax off the list.
I really don't think crypto or VR or AR are going to fizzle, I think they're just early in their overall lifecycle. I absolutely think that in ten or twenty years those categories will be much larger than today.
Ruby on Rails. Modula-2. Every JavaScript framework since ever. Supersonic passenger flight. Space tourism. Emitter-coupled logic. Gallium arsenide (still has my vote for a name for a speed-metal band). Musk's Boring Company. I'm sure I could go on with some more thought.