It'll go in stages...
First customer service,
Then replacement of call centers.
LLMs will then be incorporated into videogames... NPCs you can actually talk to who will address you by name
Then there will education... A well tuned LLM can substitute for the bottom 40 percent of grade school teachers.
The real question is what aspects of this are monetizable? The truth is all software becomes a commodity over time. LLMs will become cheap, then they will become free (they already are with LLAMA). The truly valuable companies have network effects that keep users coming back. LinkedIn, Google, Union Pacific, GitHub, Microsoft windows are all network monopolies.
From that perspective, the most valuable LLM company will be the anti-LLM companies.
Facebook, Tinder, Twitter, Instagram--- all considerably less valuable once the majority of their user bases is replaced with extremely high quality bots. The real consumers may gradually sign off and take their money elsewhere. In that world, a naive person would try to build a bot detector. But a good bot detector can simply be used to build a better bot. Instead, to win at this game, I think the most important way to win with LLMs to devise better forms of human authentication!