I think it also doesn’t help that he’s not really infusing much of what we’ve been show to be Philip into his take on Philip. Matt Smith really created an identifiable character out of Philip and Tobias Menzies took up right where Smith left off with an almost seamless continuation. That was a very believable transition from actor to actor playing the same character. Jonathan Pryce, as good an actor as he is, really feels like he’s just phoning it in as Generic Old Royal Guy. I mean, he definitely has less of the spotlight on him this season, making it more difficult to establish the character, but even in his horse carriage episode he just felt blah to me. That’s my take, anyway.
I do want to say that I am glad to live in a world where I have seen both Tony Soprano and Queen Elizabeth each be given a Big Mouth Billy Bass as a present. For some reason, that just warms my heart.
Not sure if this is the right place to post this, but I came up with an idea for naughty bedroom role playing scene between the Queen and Prince Philip.
Prince Philip pretends to be a poll worker and the Queen pretends to be voting in an election. For added comedy their servants have set up a voting both for her. 
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This is both fun and sobering; a royal letter from the time of the Blitz in 1940. Colman played then-Queen Elizabeth in Hyde Park on Hudson, as well as her daughter on The Crown, of course: https://www.youtube.com/watch?v=5jHTOInw6KQ