Using the attached screenshot of a Thread by Benedict Evans as a starting point, let's do an up to date to today deep dive into the tablet space and market.
I agree with Benedict, as a mainstream device tablets - despite selling in significant numbers - remain a bit of a misfit.
For people who have only one device (because they can only afford one, they only want one, etc.) that device will be a phone.
For the next device people own, it's more likely IMHO to be a TV or a laptop rather than a tablet or a desktop.
After that, I think it really comes down to personal preference and needs and the third or fourth device people might buy could be a tablet.
I suspect at the highest level the hierarchy (of device needs/purchasing) is:
Phone > TV > Laptop > Tablet > Desktop
Let's get the actual data on multi-device ownership and crucially usage. For example, when Google launched the Pixel Tablet with the charging/music dock they said they built the dock because their research indicated that a lot of tablet just end up lying around uncharged and unused in drawers, and by making the dock a central part of the UX it hoped to support more (and more diverse) usage (e.g. as a home hub, though arguably this is itself and niche use-case).
Let's segment the market as:
- Tablets & 2-in-1s overall
- iPad
- Mainstream Android tablets (e.g. from Samsung, Lenovo, Google and clones)
- Huawei and Honor tablets (because they run a forked version of Android)
- Amazon tablets (because they run a forked version of Android) including e-Ink Kindle devices
- 2-in-1s e.g. Microsoft Surface and similar
- Niche and speciality tablets e.g. Daylight Computer, non Amazon e-Ink devices (e.g. Boox, Remarkable), rugged tablets
Let's consider both personal usage and non-personal usage (e.g. both small business such as restaurants that use them for booking and delivery management, as well as large businesses using them in an enterprise context. Who's using tablets and what are they using them for?
Let's take a global POV, though I know reliable data from/about China is hard to come by so make a judgement call on whether or not to include China.
Lastly, to Benedict's point around window/app management, let's include a section on the UX/UI of tablets e.g. the tension that pulls them towards single use-case (at a time), focused devices vs. general purpose devices (which is hard to accomplish without a built-in hardware keyboard and mouse, but then they just end up competing with laptops).