I don't know. 465 million seems still steep for 8 episodes TV show. I am all for it cause Disney has seemingly skimped on their CG budget for their newer shows. So more competition means more TV shows will have film quality production.
But it is a concern, if their show costs more than something like Avengers: Endgame which had some of the biggest actors in Hollywood involved in addition to the probably insane VFX budget.
Obviously COVID would have affected the budget for the show, but I have a feeling that it went way over budget than was initially intended.
Although I agree with the marquee concept. HBO had their own marquee show: Game of Thrones, though it produced a lot of quality stuff like the Pacific, Band of Brothers, Sopranos etc that can be watched for years to come. Game of Thrones on the other hand was a big disappointment for the fans and its negative reception probably made HBO wonder what they would do after it was over (hence the Targaryen origin show and the Jon Snow series are being developed... personally I'm skipping both)