> having control over the whole product gives you advantages others won't have
And that is exactly what you abandon, as a user of locked-in software.
I concur infsofar, as there is a set of real world applications, where the advantage you describe really counts. Industrial control systems or hardware for medical applications for example.
Note: I own no Apple products except for an original iPad given to me on my birthday. I built my own systems from scratch, as a former electronic engineer, and create web sites on FreeBSD.
Now say that again.
Even the most literal "new Internet Explorer" -- Edge -- is a more standards-compliant browser than Safari, which has stagnated far behind every other competitor in the list.
So yeah, I don't mind saying it again: Safari is the new IE6.
Oh, and while you're on that page you linked, click over to "mobiles" and observe that even Blackberry scored higher than iOS (i.e. Safari, since you can't really get any other browser there).