This is the biggest issue for me as well. Seems that the OCR has to be triggered manually, for each page of each notebook. Which of course I don't remember to do and now there are too many.

The search doesn't appear to search across notebooks either.

The experience that I would want (expect) is that OCR happens in the background, all the time, no need to trigger and that I can then search for a word/string and find all the notes on that topic.

I've fallen back to tags and dates in filenames to have any chance of tracking down old meeting notes.

Well, you can do OCR while using the device but... it's not on device. The device has to be connected to the Internet for OCR to work. I've never checked where does it connect to do it, as I never use it...

but the result is not subsequently used for full text indexing and searching (on device or on desktop) therefore it's useless

Yep, totally.