Exactly. It's not that I don't see value in online alternatives, but in this case, if the main point is to access it offline, I don't see how different it is from a physical journal.
- editing and reordering text
- attachments
- aesthetics
- accessibility
- hassle/weight optimisation
Accessibility, because not everyone is able to hand-write in the first place.
Weight optimisation, because if a laptop is non-negotiable, going digital means one less thing to remember about and carry with you.
I have multiple physical notebooks/calendars and a digital commonplace book, they all have their place.