It sounds like Nokia looking to continue and maybe focus on its nano technology and graphene. Graphene study where it leads in Europe and was granted 1.35 billion dollars to study last year.
Having a software platform for lets say wearable tech sounds reasonable and example HERE car platform is already being build on Qt.
That said, buying Jolla would mean they are buying into a traditional smartphone market and I don't think joining that game with old tricks makes sense. Imo price structure on smartphones will go through some huge changes in near future. As long as somebody doesn't find a new blue ocean like Apple did in 2007.
MS was kind enough to take the c**p out of their hands so Nokia can continue to do other things.