[Arnt]

So what?

Pretend that you know someone at your bank who can answer the question "what devices do people use for your online banking?" You don't need to really ask, you already know the answer: For a while it was overwhelmingly Windows on PCs/laptops, now Windows has been pushed to a minority position by smartphones, tablets and macbooks.

You might say that those don't count, but I think that for a device manufacturer they do count. I have private and work smartphones and laptops, mine are made by three different manufacturers, all three make both phones, tablets and laptops. AFAICT that's typical. There are exceptions (such as Dell) but overall, the markets overlap so much that most manufacturers need to regard it as one market with different nïches.

[wavemode]

They are not one market, in any sense. The vast majority of adults in the country own both a computer and a phone. I'm not sure how they could possibly be treated as competing with one another.

Within the market of personal computers (not the fictional market of personal computers combined with other devices that aren't personal computers), Windows has very dominant market share.

[consteval]

> They are not one market, in any sense.

I agree, but there is a venn diagram here. Many use cases are covered by both products. As time goes on, the venn diagram gets closer to a circle. An iPhone of 2008 was a niche device, but nowadays you can complete 99% of tasks completely on an iPhone (yes I made up 99%, just pretend it's some number higher than it once was).

I think, for most adults, their primary personal computer is a smartphone. Many, not sure of the numbers here, don't own a laptop or desktop at all. They may have one for work, though.

[Arnt]

I'm curious… if many uses cases are covered by two products, don't those two products compete? If two products compete, how can you think that they're not in the same market in any sense?

To my mind, my ultralight private laptop is more similar to a many tablets and two-in-ones than to the 16" Macbook Pro that I was issued from my employer. Saying that the two laptops are in the same market and the tablets/two-in-ones aren't in that same market… just doesn't make sense to me.