Is there any evidence of this? All the sites I've seen that use extra requests to load text always seem to take multiple seconds to load. Whereas most pages that use server side rendering generally load under 100ms.
It's a tradeoff, basically the question is "Will most users need and read all the content or not". Displaying everything at once without making extra querries is best, but not always possible . The frontend is fetching the backend. So it's going to say "Hey, send me all the comments from all the posts from november 2021". If there are 3 it's fine, but if there are like 23,000 of them you can't really load everything at once , that's why we use pagination on the backend. We say "Hey send me results 1 to 25 of the comments from all the posts from November 2021" This way the frontend only displays 25 comments for a quick page load and we hope that it will be enough. To display the other comments either we ask the backend to let us know how many pages of 25 elements there are and we display that amount of pagination element links (pagination), or we simply tell the frontend to ask the next page once we reach the bottom (infinite scroll). Even if displaying all the content is possible, if there are content that only 1% of your users will read you might want to offer faster loading for 99% of users and add a few seconds of loading for the 1%.
>This way the frontend only displays 25 comments for a quick page load
Many years ago smart frameworks implemented smart stuff like you can display only what is visible. For example you could have a table with 1 million rows but in your html page you will not create 1 million row elements, you can create GUI widgets only for the visible part, as the user scrolls you can recycle existing widgets.
As a practical example , you go to a yotube channel page and they load only 2 or 3 rows of videos and you have to scroll to force more to appear, this means you can't do a Ctrl+F and seatrch and is also less efficient because as you scroll the items at the top are not recycled and reuse so probably more memory is used.
The json for all the videos is not huge,some strings with title and thumbnails, maybe some numbers but the issue is that is not possible to natively do the best/correct thing, only recently we got lazy loading for example so basicaly html was desibned for documents and frameworks/toolkits designed for apps did the correct thing many years ago... this is an explanation but no excuse why things are such a shit show with pagination today.
