The difference is that all of those had real products early on. The web was changing how people and businesses interacted by the mid-90s, despite computers costing far more and network access being limited and both being terribly slow. Search was a huge deal shortly afterwards, changing how people shopped, researched, etc. ML/AI has had ups and downs but we also live in a world where machines reading text, organizing your photos, responding to natural language queries, etc. are routine.
In contrast, the blockchain world has consistently failed to produce anything which many people want to buy. The lure of high returns on speculation has attracted more people than any of the products, but there's no durable business hook the way there was for, say, going back to buying plane tickets over the phone.