An engagement between CP and Sophia will make the downhill steeper for sure.
The royal family is in a delicate position. King CG opened the door to accept marriage with commoners when he married Silvia Sommerlath (and actually thanks to her the royal family gained popularity again…). Therefor he can't really deny his childrens' partners a titel.
Today when people more and more are questioning the existens of a monarchy for just PR and historical reasons it would give rather weired signals if CP and/or M gave up the titel - for any reason (even if they really should consider it regarding the amount of "work" they put into it). Why should we keep a monarchy if not even the royals want to be royal? Or "qualify" to be royal (if for example CG demands that CP and/or M loose the titel - which I doubt he will)?
CG might temporarilly get away with giving Chris and Sophia some duke/dutchess title and keep the prince/princess titels to Victoria and her kids - with the argument of not ending up with too many princes and princesses in a few years when CP and M start breeding. Still, that would go against the fact that Lilian became princess (although they married before CG and Silvia had ”produced a heir”).
There really is no ”right way”, either way I do believe we’re on the path to become a republic. I honestly wouldn’t mind!
...I hope I'm making some kind of sense, sorting my thoughts into written words

Not sure if this is the right thread for this either, but I figured that one with the words ”Monarchy” and ”Crisis” would fit quite will…