Thanks for actually booting one, that's the bit I skipped.
-84s versus -10s without console=ttyS0 matches the Ubuntu ratio, and it's the first EL10 number anyone has measured rather than read from the source.
That settles the question I left open. A real-world measurement is vastly better than a source-code read, right?
Thanks for the backport request, too. Since CentOS Stream sits upstream of RHEL and Rocky, if the backport lands there, it should be the earliest signal that the rest of the family will follow.