Whew! That is good news indeed for a lovely king!
Reflecting upon Great King Harald: IIRC, Harold threatened not to marry but continue with his royal duties if he could not marry Sonja while others in similar positions threatened to quit.
Why was she considered unsuitable? That's really interesting that he, if I am understanding this correctly, basically said that if they couldn't marry, he'd fulfill his responsibility as king but don't expect any heirs and good luck when he's gone?
That is pretty much what would have happened. Until 1990, male primogeniture applied to the succession. Harald had two sisters. Absolute primogeniture would have had to be enacted at some time whether Harald had direct descendants or not. Frankly, Harald just probably gave people enough time to get used to the idea that his consort was going to be Sonja or outlive his father. They did break up at some point as a result of the opposition to their marriage.
But supposedly they really wouldn't have been allowed to marry and Harald stayed single.
Then what? At his death there would've been no heirs. Would've they've allowed Ragnhilds line to inherit? (commoners as well) Or would they've looked further to the Danish Royal house? Or become a republic?
The Succession law, until 1971, excluded Astrid & Ragnhild.
According to the Succession law, there should be only one king, with primogeniture as a rule. If the oldest son was not fit to be king, a council of sixty representatives should select another of the legitimate royal sons. After this they could choose between another of the royal heirs. If the king had no suitable heir, the council could choose whoever they thought would better "guard God's right and the laws of the land". If the representatives could not agree, the bishops of the Church should decide the election.
Times were a changing. Daisy married an almost commoner.