I don’t see the problem with Pryde saying Palpatine & co. “conjured legions of Star Destroyers”, I don’t think he means that they literally materialized the ships out of thin air. It’s just a riposte to that other officer calling them “conjurers”, he’s simply stating they have brought forth a large & previously unknown fleet, as if being “conjured”.
In any rate I don’t think Pryde would be privy to the inner machinations of the Sith Eternal and their ‘fleet conjuring rituals’, so I don’t see how this line could be read as him explaining the origin of the Sith Fleet.
On the other hand, Kylo was the only person who even went to Exegol (as far as we know), so all any of them would know is what Kylo told them. Why would Kylo, in his official report, say that Palps had “conjured” Star Destroyers if he hadn’t? I’ve always interpreted as Pryde being literal (not to mention, it’s the closest thing the original film offered to an explanation for the Sith Fleet’s existence).
Personally, I’m not super concerned about this either way. If Pryde/the script wants to say that the Sith Fleet was conjured…fine, whatever. It’s not the stupidest thing in the film by a long shot. But if Ascendant does want to downplay that whole aspect…like Chase said, it would probably be more in line with that goal to trim the line.
Plus, the intel from Hux that Poe shares outright states that they’ve been BUILDING the fleet for years.
And even then, one possible interpretation of that statement is that they’ve been building ON the fleet. As in, there was a stockpile, but they’ve also been expanding upon it and upgrading the weapons (BTW this is the answer that I think makes the most sense because it’s a hybrid approach).