I agree that it reflects badly on Charles if the DoE doesn’t go to Edward in some form; as Somebody said below, Camilla has had a promotion from what was agreed and announced and as it stands, Edward has effectively had a demotion despite being a key part of The Firm until the King’s grandchildren are of age, being much younger than his siblings together with the lack of public appetite for Andrew and Harry to serve.
As I understand it, Philip approached Edward about becoming DoE in the lead up to his marriage. There was no guarantee at that time that there would be children of the marriage for the title to be passed down any further than Edward; he married later than his siblings, with Sophie being less than a year younger than him. They then suffered an ectopic pregnancy two years before Louise was born prematurely. In any case, like his grandfather and brother before him, there might have been heirs but no male heir. All Philip could be sure of at the time was that Edward would be the only child who might be able to pass the title on.
I haven’t said that I think James shouldn’t be a Duke, I simply described the two alternatives that have occurred to me as to what might happen with Edinburgh, and the rationale behind them. Charles is going to care more for a future role for Louis than his nephew becoming a Duke in time and ultimately he has the power to do that if he wishes. The situation with Harry is probably weighing on his mind, it’s not something that he could have foreseen at the time he presumably indicated to his parents that he would create his brother DoE and as such he’ll be keen to ensure that Louis doesn’t resent that his brother will be King, his sister will be Princess Royal and it’s just him left without anything or with any old Dukedom. Indeed, if DoE does go to Louis exactly as created prior, it will eventually end up further from the throne, it’ll just take longer.
On balance, I am thinking that a grantee only approach would be a good solution as is the case with Princess Royal, that way Edward gets what was promised to him and DoE stays relatively close to the throne and will be available for use in the future. We cannot really know what was meant when Edward described it as a pipe dream of his father’s, whether he was never really that keen on it but did not want to hurt Philip’s feelings as he would have known how he felt about not being able to give his name to his own children; whether he was honoured to be asked but has since gone off of the idea or whether it is Charles who has indicated that his vision for the DoE has changed.
Edward might himself feel quite conflicted that any titles that he can pass on will go to his younger child, with nothing for the elder, knowing that his brother’s approach is to modernise the monarchy. I have no reason not to believe the reports that Edward specifically requested Wessex and I can see that he might like to continue using it (but of course he could have DoE and still choose to be known as Wessex, his own children use lower titles than they actually hold.)
I completely agree with the poster above who mentioned that it would be difficult for someone to run the awards without James’s involvement if he was DoE. There might then be an expectation for him to use HRH Prince, which he may not want. Peter Philips would also be the only one of the Queen’s grandsons never to have a Dukedom. Not a good look for a modern monarchy. He likely doesn’t care, but still.