A Wacom Graphire tablet! This was in the early 2000’s, and my friends pooled their money to get it for me because they knew I liked to draw. I made graphics for all of my clubs and orgs and then ended up working as an illustrator through college and beyond. I used the original tablet until it broke and then moved on to the Intuos. I actually don’t draw anymore but that was definitely one of the most thoughtful and well-used gifts I’ve gotten.
I can relate to this. I have a hard time with many books even if I am interested in the subject; interesting content doesn’t mean that that content is easy to get through or engaging throughout.
I usually read a few things at a time and I’ll often choose these types of books to listen to when I’m doing chores and errands. I might not feel motivated to sit down and give the book my full attention, but I can handle an hour or two of passive listening. The downside of having my attention split is that I will definitely miss things and have to pause and go back, but that doesn’t frustrate me nearly as much as when I’m fully concentrating and still find myself rereading the same paragraph without absorbing anything. It might take me several hours to listen to a book that should theoretically take me half the time to read, but in the end I’d rather have finished the book however long it took! This doesn’t work for highly technical books where you really need to have the text in front of you the entire time, but I haven’t had problems with the type of non-fiction you’ve mentioned.
Another thing that really helps me is having the book in both text and audio formats. I’m able to retain the information much better if I listen and later skim through the text I covered to note what stuck out to me. It’s a bit of a waste of library check-outs, but having the ability to switch between formats helps me get through the material faster. It sounds like a chore but it doesn’t actually take much time to do.
Lastly, sometimes I do just lean into the “boredom” and read a little before bed since there’s no risk that I’ll binge the book and stay up all night.
It sounds like you’re already doing a lot of this (audiobooks, notes) so if that’s the case, I guess the main thing that helps me and might hopefully help you is just being okay with the glacial pace and extra effort?