I tried both Mayan and Paperless (regular) myself to replace my Evernote Premium setup, they haven't convinced me yet.
I am currently trying out https://github.com/jbarlow83/OCRmyPDF myself (had to fork it to add my own language to the Dockerfile) and then will either let my NAS index it afterwards or Dropbox/Nextcloud maybe. Apparently locally they get indexed very well with either Gnome (Linux) or Finder (Mac) or Explorer (Windows).
I like the idea, reminds me of the "Smart Contact Reminder" (https://play.google.com/store/apps/details?id=me.barta.stayi...) app for Android. Too bad this one is not available for Android (yet?). However, there is definitely a market for a Personal CRM like this. Desktop access would be great. Maybe even like a web-app like Tinyblue (https://tinyblu.com)?
Maybe this is the reason he did not appreciate people revealing his identity online (basically DOXing him for fun, some journalist did it if I recall correctly). It really sucks when somebody that is trying to do well (stopping the WannaCry Ransomware as he did) is detained, even though we don't know more details at this points, this hits him rather personally and probably not for the good, I am very sorry for him and I hope he gets out soon and that all is well.