Businesses, even very capable with web dev, update their websites very rarely. Businesses want to update the content, which is different. Static site generators are built exactly for that.
Can I open an app on my phone to create/update a post? Can I Use my phone to create another user so a friend can guest-post on my blog? Can I send an email to a certain address to publish a new post?
Now you just take things a blogging platform can do and try to morph that into an argument against static site generators. The very point of static site generators is to drop a whole host of functionality.
How often does a construction/handyman "online flyer" webpage need a change? Once a year, maybe. The primary point I am trying to make is that websites of a lot of small business (obviously ones that are not webshops) serve more or less static content and therefore have no need for a backend at all.
You have a food blog where you publish recipes/reviews daily? Surely a blogging platform is a much better fit for you. You have a restaurant page where you publish contacts, coordinates and a menu which changes every second year? Well, maybe a static site generator is a better fit.
