Hi @ jacek ! My name is Kaniz, and I'm a technical moderator here. Great to meet you, and thanks for your question! Let's see if your peers on the Forum have an answer to your questions first. Or else I will follow up shortly with a response.
Heh yeah this is a good observation. The title feature is kind of forgotten, and in a way subsumed by Markdown support, which exports and can be read with other tools. It might be a little unclear how to merge the two - what level are they at? but I could see generating a ToC at least if there are only cell titles. That said I'd recommend markdown in general.
@jacek - I wanted to pop in and give you a status update. The team is aware of your request. I can't make any promises on when something may change, but we appreciate your idea and bringing this to our attention.