People have a limited amount of time and energy.
When I was younger, I learned all the computer stuff I needed, built my own computers and so on - and in those days, there was no such thing as "plug and play". If you youngsters even know what that means (see also: "Asking fish about water"). Then came work, and a family, and laundry, and a garden, and a household budget, and there were some interests other than computers and gaming. Of course I can still learn what I need as I go along, but it takes time and energy. Unless I get results reasonably fast, I hand it over to my husband who does those sorts of things professionally. He does this too, for things where I am more proficient: sewing, cooking, important writing, and so on. Sure, my husband is perfectly capable of fixing the length of new trousers himself. It's just so much quicker to let me do it, and the results are more consistent.
Specializing saves time.
(But gaaaaaah for all the times my father-in-law calls for computer help. He has many, many admirable skills, but reading all the words in an error message isn't one of them.)