what I understand:
inside Jolla, most would like to open source more but the board has not decided it yet because it seems that new investors/(industry)customers may be reluctant to come if too opened. Probably that is what some of interested parties told them. At the end, I guess it all depends on if someone join the party (and invest in Jolla) and who it is.
Short-term vs long-term is probably because if they cannot get it in the short-term, they hope to get in the longer term (even if that is not that clear how it could be easier in the longer term).

There are probably on-going discussions with other parties and we will not hear anything till they have not finished to discuss. I am quite sure that being more opened is not the main point of the discussion though