I think it's fair because AWS charges extra for it.

They are comparing the baseline product of all three platforms. Why should we take paid add ons into account for 1 platform.

As I mentioned, if you are ok with paying, then you should also compare Provisioned concurrency on AWSbas well, which has 0 cold start (they keep a prewarmed lambda for you).

Product comparisons are not purely technical in nature. As a user, if im paying extra, I would much rather the 0 cold start than just a reduced cold start especially with all these additional complexities.