Posting in case there are any datapoints that matter for the community. Experian - 743, but young file, many inquiries. I have a positive but short (~6 month) history with Amex. I had been waiting until inquiries age off in 2021 to get a CSR. When the CSR AF recently went up, I decided Platinum made more sense for me. I did not have a preapproval, but I applied via Corporate Advantage Program anyway and was (to my mild surprise) denied. Today, I noticed that I did have a preapproval, so I applied again via CAP and was approved. Come to think of it, I got my first Amex card on July 17, so maybe going a day over 6 months made the difference. Don't mind having to apply twice since the denial was SP. So far, the approval also seems to be SP, but that may change.
Via CAP, I get a $150 annual statement credit for Platinum and a $100 annual statement credit for Gold, so it's like I pay normal price for Platinum and also get Gold for no AF. The Platinum SUB is the normal 60k one, though, not the coveted 100k. I decided not to wait for it, as I want my stuff to age together to the extent possible.
I am planning to downgrade my Hilton card after the AF hits again. The only other thing I want to do as far as credit cards is get Ducks Unlimited when most of my inquiries are more than a year old. And of course, increase my CLs.
Congratulations on your approval!
Congrats on your Amex Platinum approval! Enjoy the travel perks! 
Don't be fooled by my score. It is a paper tiger. I have heavy credit-seeking and over 15 inquiries per report that are all under a year old. I've seen quite a few other people get Gold Cards, which I assume have basically the same underwriting, with scores in the mid-600s.
You may know this already, but the score they focus on is Experian. Good luck if you do apply!