Each account within the organization gets the limits of the free tier, just as a single account would. I think the reasoning is that if you're going to go through the hassle of setting up orgs then you're probably an enterprise user slated to take the long haul anyway.

Not true, the free tier is applied at the Organization level (i.e. the billing account), not to each individual account.

Hmmm according to https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2... it reads that it should be, but the wording is opaque. Hopefully someone from AWS can answer.