Why do people insist on comparing the initial frontload of a SPA to the page load of every page in their SSR web app?
Once a SPA is loaded you can send tiny crumbs of data faster than any significant SSR.
Once a SPA is loaded you can send tiny crumbs of data faster than any significant SSR.
You can, but often that's not what's happening.
E.g. crates.io is currently built as an SPA. It is first receiving a HTML page that loads a javscript file, that performs an XHR request (actually, multiple) that answers with JSON that is used to create the final DOM of the page. The Javascript file is cached but that's about it, it still involves one additional needless roundtrip for the website.
The JSON sent is so badly designed that it alone is far more than the final DOM of the page.
Jus check out this: https://crates.io/crates/winapi
vs this: https://crates.rs/crates/winapi
Only the XHR requests for the crates.io page take up 99 KB uncompressed, while the entire crates.rs winapi page takes 103 KB uncompressed.
Because a user doesn't care if it's the initial frontload or not.