some people who used to have a high-skill job will have their skill be devalued as AI takes over - this is a consequence of technological improvement. It is not a right that society maintains a level of value in an acquired skill. They will have to adapt.

As for fewer farmers, that is exactly it - those who would have been farmers would be required to acquire new skills or pursue something other than farming. Bringing this back to AI - artists, writers and programmers who get displaced will need to adapt. In the long term, the massive decrease in costs of production of various "creative" endeavours will produce new industries, new demand and increase overall wealth - even if it is not shared evenly (in the same sense that past technological leaps are also not shared evenly).