Google Glass comes to mind, which died 11 years ago and XR is only just now starting to resurface.

Tablets also come to mind, pre-iPad, they more or less failed to achieve any meaningful adoption, and again sort of disappeared for a while until Apple released the iPad.

Then you have Segway as an example of innovation failure which never really returned in the same form like the others, and instead now we have e-scooters and e-bikes which fit better into existing infrastructure and cultural attitudes.

It's quite possible LLMs are just like those other examples, and the current form is not the going to be the successful form the technology takes.