Even relatively small businesses in my neighborhood with not much cash to spend start out with a 'cheap WP' site, but then they want reservation systems integrated with their CRM. They want a live chat system. Integrated with their CRM. They want their reservation system connected to online partners. Etc. In a few months after starting out with this site, WP or anything else is no longer relevant; existing solutions need to be integrated manually anyway and custom solutions made by, for instance, the CRM/reservation system which do not use WP are a better fit. At a much higher price. And people pay it, because custom integration is even more expensive.
Even with all it's plugins, WP is only a good solution if you like to do a lot of work manually or you want to spend a lot of money having every plugin and external package nicely integrated. And no inexperienced programmers is going to bring that to a good end without landing on reddit/hn as being responsible for making some epic security holes along the way.
It's not a case of developers being automated, it's a case of the customer not understanding that they get what they pay for.