I feel like Aman Tokyo is charging the rate based on availibility (and some others in Tokyo too), not by seasonals like Aman properties in another countries. They will keep increasing the price and surprisingly people are still willing on paying for those rates. Quite make senses I guess to keep the hotel from full capacity so they can keep up with the service demands.
Then there is a new Janu, same city hotels within one place. They will keep going to upmarket and can't lowering the rates again like pre-covid cuz it's Janu's range now.