I think all startup/business advice can be qualified with "...unless you're Steve Jobs."
I think it's generally good advice, but if you have the wherewithal to execute a combination product to perfection, then you'll win. The point is that people who focus on any one aspect of your combination product usually will do better.
Think toaster/microwaves or scan/copy/fax machines.
Also, Apple has been a "several"-hundred billion dollar company for a few years. They have the clout to do things that are not in same universe as several-hundred thousand dollar startups.
I think it's generally good advice, but if you have the wherewithal to execute a combination product to perfection, then you'll win. The point is that people who focus on any one aspect of your combination product usually will do better.
Think toaster/microwaves or scan/copy/fax machines.