I agree that Apple shouldn't be chasing every bit of chickenfeed and producing lots of similar products. In fact, I would like to see Apple go back to 4 main macOS products; home desktop, home portable, pro desktop, pro portable. Getting rid of the MacBook Air/MacBook/MacBook Pro/iPad4/iPad Air/iPad Pro/iPad Pro2 confusion would go long way to making it possible to recommend an Apple product to my friends & family.
As it stands now, when someone asks me what computer to buy I have to interrogate them on their exact usage pattern and then spend a couple of hours looking at all the different Apple products to see which one might serve them best. 10 years ago it was simple; you just want to send email, browse Facebook from home, get an iMac. If you wanted to compile code at Starbucks, get a MBP. Goofing off at the library, get a MB. Simple.
The Apple product line has expanded because their user base has expanded. They're no longer selling a few hundred thousand Macs to a few categories of creative professionals. They're selling many millions of them to people all over the world.
Even so, Apple to this day doesn't chase after every conceivable ecological niche in the market. They only sell two headless Mac models (ignoring internal component options). The Airs are likely on the way out, so their clash with the MacBook is likely just a temporary transitional thing. Many of the products you listed are actually just different generations of the same thing.
As it stands now, when someone asks me what computer to buy I have to interrogate them on their exact usage pattern and then spend a couple of hours looking at all the different Apple products to see which one might serve them best. 10 years ago it was simple; you just want to send email, browse Facebook from home, get an iMac. If you wanted to compile code at Starbucks, get a MBP. Goofing off at the library, get a MB. Simple.