The MP3 spec was defined a decade before we had iPods. Spreadsheets took a decade to become indispensable to businesses.
Clifford Stoll had used the internet for two decades before writting his infamous 1995 essay in Time saying the internet was overhyped, and "normal" people would never e-mail because they can just fax.
CRISPR was first observed in 1987, and the gene-editing breakthrough came in 2012.
It's really, really unclear why you think LLMs would have faster adoption, when they are already that being adopted faster that anything other tech, ever.
Do you honestly know of no non-technical person who use LLMs? Because an absurd number of people report on surveys that they use it every week.
LLM apps are regularly the top downloads on the iPhone.