I had an Irex. The company went out of business a few years later. It had an 11" screen, very high contrast, supported note-taking over any kind of content, and had a nice modules API.
> Most eReaders have been 6" since the days of the Sony Librie.
7" readers were common when I brought my current one, but nowadays there are only 6" ones out there. A bit before I brought mine, there existed 8" ones, and Amazon launched an interesting A4 sized one.
You had a very niche device at the time that was far from the typical reader of 2010.
7 and 8" inch devices very much still exist. Kobo has the 7" Libra Colour and the 8" Sage. Amazon also moved the popular Paperwhite line from a 6" device to 7". Pocketbook has 7 and 8" readers. 7" only got MORE common if anything. Six inches was the most common eInk size for a long time.
You can still get big format devices with notetaking. Now the big brands like Amazon and Kobo have them in addition to smaller players like Boox or Meebook.
That's very much bigger than a book, so I think that's probably why it's harder to replace.
There are still large format paper devices. Kobo Elipsa 2E for $350, Remarkable 2 for a touch more, etc etc. They're not sold as ebook readers, but you can read books on them fine.