I have been thinking about this a bit more. I think the World of Hyatt is the only thing making the Chase UR currency highly valuable. At the same time, I think Chase UR earning is the only thing that makes World of Hyatt a credible earn and burn program. I am not convinced either relationship is particularly financially lucrative; however, they complement each other nicely from a consumer value proposition perspective.

The biggest issue with Amex MR is the lack of decent options for hotel redemptions. Hilton points are worthless and the Hilton portfolio is likely to be largely unappealing to many of the biggest natural spenders at Amex (I know Hilton is super popular for manufactured spenders). A 1 MR: 2 Bonvoy would solve this issue entirely. Again, I highly doubt Amex would ever do this because it doesn't seem they have a real incentive to worry about this problem.

With a 1:2 transfer, Bonvoy would become competitive with even Hyatt from the earn and burn perspective.

St. Regis Bangkok cost: 35K points standard
Park Hyatt Bangkok cost: 20K points standard

To get a free night at the St. Regis, you would need $4375 in grocery/dining spend on the Amex Gold or $3500 in airfare spend on the Amex Platinum.
To get a free night at the Park Hyatt, you would need $6,666 in dining spend on the CSR or $4000 in airfare spend on the Chase travel portal (not ideal to book through IMO) or through Chase freedom categories.

Ritz Carlton Shanghai cost: 60K points standard
St. Regis Shanghai cost: 35K points standard
Park Hyatt Shanghai cost: 20K points standard

To get a free night at the Ritz, you would need $7500 in grocery/dining spend or $6K in airfare spend.
To get a free night at the St. Regis, you would need $4375 in grocery/dining spend on the Amex Gold or $3500 in airfare spend on the Amex Platinum.
To get a free night at the Park Hyatt, you would need $6,666 in dining spend on the CSR or $4000 in airfare spend on the Chase travel portal (not ideal to book through IMO) or through Chase freedom categories.

St. Regis New York cost: 85K points standard
Park Hyatt New York cost: 30K points standard

To get a free night at the St. Regis, you would need $10,625 in dining/supermarket spend or $8.5K spend in airfare spend.
To get a free night at the Park Hyatt, you would need $10,000 in dining spend.


The New York analysis also applies to other top-tier cities/travel destinations like Tokyo/Maldives/Whatever

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It's pretty apparent I have a lot of free time this morning given my analysis of a hypothetical program that is likely never to occur. However, it's really sad that doubling the current earning rate of the Bonvoy program is the only way it can come even close to being competitive with World of Hyatt. Also, all of this assumes base earn. The WoH program is the easiest to churn through Chase UR given the insane UR bonuses Chase has with the CSP and the Ink cards. You can grind 1 business card every month...

Marriott limits you to 2 bonuses per player for the first 2 years then just 1 bonus every 2 years afterward.