Way too simplistic view.
> increase supply
Not necessarily. Supply could stay the same.
> drives down prices
Not necessarily, if raw materials got more expensive.
> The only negatives are on the individual
You might want to have a look at youth unemployment rates. Sometimes, there simply are no jobs: https://ourworldindata.org/grapher/unemployment-rate-for-you...
Changing careers reduces your income and your purchasing power. If it happens to too many people at once, standard of living decreases.
You simply neglect demand in your entire argument.
But layoffs only occur if firms can produce output at a lower cost by using AI rather than humans. Those humans go and work elsewhere and total output increases.
Try LLMing this (it efficiently interrogates both your assumptions in a single prompt):
> in standard economic thinking, is it possible for a job to be made redundant due to improvements in technology and that employee to be reassigned elsewhere, and for either long run supply to go down or long run prices to go up?
Note: there will always be edge cases, for example if I owned a business, I could theoretically replace someone with AI, and increase my prices, which would contradict the idea that greater efficiency always results in more supply and lower prices, but overall in the long-run that won't happen.