There are actually two parts to it
a) Number of requests/day number mentioned here https://learn.microsoft.com/en-us/power-platform/admin/api-request-limits-allocations - This number is actually 400 per authenticated user per day (for new licensing), so what this means is for each pack of 100 users, you get 40,000 requests/day for your site.
For anonymous, it is 80 per user/day, so again for a pack of 500, you get 40,000/day.
This does gets counted in non interactive quota and only applicable for your website. This is missing in the doc right now and i will get it updated.
One important thing here is this is not enforced today.
b) Service protection limit of dataverse : This is the 6000 request/5 min number. But this number is per server and number of servers are determined by the licenses you have at tenant level (Pages, dynamics or Power all combined). So this number is directly tied to your licensing.
This is enforced.
There is a third thing which we don't mention explicitly which is front end web servers you get for each website (different than dataverse servers). This is directly determined by the power pages capacity you have assigned to particular environment.
Important thing here is this si what you assign to env and not what u have at tenant level. This we don't talk about in documentation today apart from a bit in our architecture white paper. But we will try to add some details around it soon.
