This is all technically true, but I think discussions around market share of personal computers and phones can be a little misleading sometimes because Apple has typically avoided high volume, lower end "commodity" markets. Windows and Android numbers are heavily padded out with low end office computers, netbooks, and cheap or "free" phones. What was the single best selling phone over this past year? The iPhone 11, and it wasn't even close. In fact, of the top 10 most sold smartphones, 5 were iPhones. Sure, in aggregate there were more Android phones sold overall across many models and manufacturers, but most are not competing at the high or even midrange. Most basic, modern flip/slider/candybar budget phones are running Android too.Apple has inched their way up in market share for PCs, but they're still a small player on a relative basis. They're sitting at 7% - well below the top 3 (Lenovo, HP, and Dell, at 24%, 22%, and 16.8% respectively.) IIRC, although it has fluctuated, Apple has never broken 10% or so, and they've been near their current number decades ago.
Of course, this isn't to say Apple isn't very successful. They are. But it's more because of their extremely high prices as opposed to dominating market share.
Apple likes the position they're in. They make most of the profits and get to avoid much of the legal scrutiny directed at dominant marketshare leaders. It's a win win situation for them. And because they're willing to so aggressively "burn the bridges behind them", the Mx chips will be very difficult for the rest of the industry to quickly respond to. Apple is one of the few companies in the world who can pull off this level of full vertical integration. Microsoft and the entire x86 software/hardware industry is shackled by decades of legacy tech debt and expected backward compatibility (which can be a good thing too!). For desktop computers where power and cooling systems can keep growing and become more elaborate as needed, this isn't as big of an immediate issue. In the laptop space they'll be in for quite a shock within the next 2 years. The M1 is just the beginning.