I foresee a slightly different outcome: If companies can genuinely enhance worker productivity with LLMs (for many roles, this will be true), then they can expand their business without hiring more people. Instead of firing, they will slow the rate of hiring. Finally, the 250 USD/month license isn't that much of a cost burden if you start with the most senior people, then slowly extend the privilege to lower and lower levels, carefully deciding if the role will be positively impacted by access to a high quality LLM. (This is similar to how Wall Street trading floors decide who gets access to expensive market data via Reuters or Bloomberg terminal.)
For non-technical office jobs, LLMs will act like a good summer intern, and help to suppress new graduate hiring. Stuff like HR, legal, compliance, executive assistants, sales, marketing/PR, and accounting will all greatly benefit from LLMs. Programming will take much longer because it requires incredibly precise outputs.
One low hanging fruit for programming and LLMs: What if Microsoft creates a plug-in to the VBA editor in Microsoft Office (Word, Excel, etc.) that can help to write VBA code? For more than 25 years, I have watched non-technical people use VBA, and I have generally been impressed with the results. Sure, their code looks like shit and everything has hard-coded limits, but it helps them do their work faster. It is a small miracle what people can teach themselves with (1) a few chapters of a introductory VBA book, (2) some blog posts / Google searches, and (3) macro recording. If you added (4) LLM, then it would greatly boost the productivity of Microsoft Office power users.