I think the issues surrounding upgrading to 6GHz is that you SHOULD do a full redesign specifically for the 6GHz. Too many places, especially schools, and hospitals continue to 'reuse' existing cable drops and do merely a 'rip-and-replace' thinking they are getting an upgrade. But since their requirements have changed since the first installation (And maybe that first 'design' never met any requirements other than a GREEN heat map...) Moving to 6GHz NEEDS a re-engineered solution.
Not to mention Tx power on 2.4GHz, 5GHz, and 6GHz should all be widely different. In fact, we normally turn OFF 1/2 to 2/3 of all 2.4GHz radios in the upgrade process.
If you are in the 'rip-and-replace' mentality... you will NOT see much benefit of adding 6GHz-capable access points!