Probably because these are not rote tasks being performed but rather new dev projects driven by new demands, priorities, and business requirements. You can’t automate that type of work.

Some things need a human touch. Interacting with other humans is one of those things. See any automated customer service bot ever to see how absolutely terrible an idea that would be.

Probably because it’s still cheaper to throw people at it.

Good luck automating fixing bugs and implementing weird customer requests in an old legacy application.