You've got things backwards: The FCC is just as sane as anywhere else when it comes to indoor low power (no requirements) but all the other regulatory agencies lack the option of something like AFC if you want to go beyond the 250 mW EIRP client limit (1000 mW EIRP AP limit). See the table on page 2 https://docs.fcc.gov/public/attachments/DOC-375609A1.pdf
You may have mixed this with outdoor use, which the FCC does require AFC for regardless of power, but I'd still argue even the outdoor regulation is saner than how most countries approached the band. I.e. rather than say "no, you can't use all/most of this 6 GHz space outdoors at all because there are some incumbents" the option of "Despite there being incumbents, you can use the band up to 4000 mW EIRP from the AP and 1000 mW EIRP from the client on the condition you tie into the AFC system to make sure you aren't interfering with an incumbent by doing so" is available.
You may have mixed this with outdoor use, which the FCC does require AFC for regardless of power, but I'd still argue even the outdoor regulation is saner than how most countries approached the band. I.e. rather than say "no, you can't use all/most of this 6 GHz space outdoors at all because there are some incumbents" the option of "Despite there being incumbents, you can use the band up to 4000 mW EIRP from the AP and 1000 mW EIRP from the client on the condition you tie into the AFC system to make sure you aren't interfering with an incumbent by doing so" is available.