But exactly as the person you replied to said, they increased the average intelligence needed to do the new jobs. That leaves so many marginal people unemployable. They could have maintained horses but working in cars is harder. I like this observation.
I'm not convinced that animal husbandry is less skilled than working in cars. Different skill, and as I've never done it I can't be certain, but horses are wet and messy biology with brains that are terrified of anything they've never seen before. Production line work I did do as a summer holiday job during my A-levels aged 17 or 18, it wasn't skilled work but also that was HVAC production line not cars.
The specialization has certainly taken off - people are much more specialized in their jobs now whereas “farmer” was really a jack-of-all-trades with passing capabilities in many different skill sets.
There is a thing to say about "unnatural-ness". Handling horses up to a point had to be more intuitive and more approachable, we've been around horses and other mammals since forever. Around spreadsheets? 40 years, max.
They actually resulted in a decrease in overall skills required. It takes a lot of skill to use a loom and make a napkin, the same is not needed for factory work yet you can make 100 napkins at the same time.
Similarly, we had the rise of the service industry in the US - manufacturing required a lot of skilled labor; retail and wait-staff do not require the same skill.
