What confuses me is how websites like www.basketball-reference.com operate. Trawling through the network tab, I can't find any call to an API that loads the information on the frontend. Maybe this is the dumbest question alive (and please let me know if it is), but how do these websites disguise the payloads from their servers? Am I just not looking in the right place, is it encrypted and then decrypted somehow on the frontend, etc.
They will most likely be rendering the page in full server-side. This is how things were done in the beginning, but also what a lot of websites are returning to, for performance reasons.
I just wanted to add:
1. The words you're looking for is "server-side rendering".
2. After a decade or so of Angular, React etc, it seems people (not you, OP) have forgotten that HTTP can transfer things other than json, like plaintext, HTML etc. Whatever really.
3. You might want to read up on the OSI model. Just something to keep in mind. https://en.m.wikipedia.org/wiki/OSI_model
Here's an example of it in go - https://gowebexamples.com/templates/
I guess my question is - what makes you think basketball reference uses a ton of api calls?
They do have some - search for example - but static sites and a mix of static sites and html works well for a lot of the web and can lower costs tremendously.