We aren't talking about licensed components which should be kept optional in Sailfish if possible. We are talking about what Jolla develop themselves. I skimmed through the log (which is quite big). What exactly do you refer to regarding problems with opening code?

There is a reference to https://together.jolla.com/question/.../#post-id-6768 in the log. It just repeats, that UI should be closed, but it doesn't discuss any problems or reasoning. In essence it is black and white. I.e. preferred approach should be, use open code, unless it's impossible for a valid reason.