In the case of Apple I think if you look at the mobile phone usage of
people in the top 25% of incomes in America you would find that they are well over 80% market share. While this is a somewhat contrived segmentation, it is also most important segment for a lot of businesses. Monopoly power is typically assessed by the doj at a regional level so it is not unprecedented to arrive at monopoly issues on the basis of a portion of a larger market. The novelty here is about switching costs and bundling.
You can't cherry-pick a market segment like that. Each successful product has a niche somewhere.
Dominant market share is not the same thing as a monopoly, because the existence of competitive alternatives is a check on the behavior of the market leader. Also, it is tough to ignore the fact that any customer can buy a Samsung phone with largely the same capabilities at a similar price point to the iPhone.
Not all monopolies are unlawful in the US. There is a need to prove that practices are anticompetitive, such as by unfair pricing or exclusive dealing. If Apple is expected to curate and support an App Store with non-malicious apps and reviews thereof, used on a platform for which they provide an ecosystem of developer tools, they are entitled to charge a fee for that.
It's inexact, but not contrived at all. If you've ever worked in online advertising, you'll know to treat apple users as a distinct segmentat without worrying to much about why exactly.
There's a reason Google pays Apple so 15 billion pa for search defaults. Adwords would be deeply hurt if Apple decided to withhold its users.
What is the technicality? It's certainly a monopoly in layman's terms.
Is the technicality monopsony? IE, the fact that Spotify have more power over artists than consumers? Is it the fact that there are other streaming services in existence, and spotify has <100%.
I feel like people can specify "textbook-monopoly," if they need to use a hyper-strict definition of one kind or another. For regular conversation, the common definition of the term works fine.
That's not the definition of a monopoly, unless we're describing some sort of textbook/theoretical concept. Spotify are certainly a monopsony in their relationship to artists/studios. The whole business model depends on and assumes market power. They're absolutely a monopoly in normal language.
And there is a difference in scale between Apple's control and everyone else's.