AWS S3
I am following AWS's Wordpress Whitepaper for a large scalable website.
https://aws.amazon.com/blogs/architecture/wordpress-best-practices-on-aws/
It spins up multiple servers as the website requires more resources. For this to work all data and assets need to be moved off the hosting environament. e.g. external DB (Aurora MySQL) and Storage (S3)
I see multiple mentions of S3 in your Forum, but with no definitive snaglist, workaround, solution or timeline...