From personal experience I can tell you that using a modern framework can be really worth the added complexity even in simple applications.
For one of my clients projects it started out in what seemed like a simple crud app and so I did the few reactive changes in pure java script. The thing is: requirements changed and now after a while I couldn't get around adding VueJS simply because the reactive changes kept piling up.
Even though the HN sentiment seems to be that all "modern" frameworks are just huge piles of code that you add to your project without understanding how any of this works, my personal opinion is that using something like nextjs with server side rendering is not all that different from using a server side php framework like laravel. You still generate the same html unless you need reactive changes and when you do, you are happy to have chosen that. And to play a bit the devil's advocate: Unless you write your own webserver and template rendering engine you are already using a bunch of code you don't really understand.
It is like questioning about backend using a spring boot in every single service even when it is only for a simple store and fetch json from mongoDB. If you have the know-how, why not? Jumping between Vanilla and React projects can be counterproductive. If things get more complex you are prepared, if not, nobody will mind.
It is not fair to compare SPA or big frontend frameworks with "pure JavaScript" or messy jQuery as some imply.
By putting 20% the effort we put nowadays with these big frameworks into well organized "sprinkles" it is a very viable alternatives. Tools such as Stimulus, unpoly, htmx,etc make this very approachable and maintainable.
To me, SPAs only make sense in two scenarios: 1) You have the requirement for the app to work offline, or on really bad network connections (subway, etc) or 2) You already have a team which only wants to do SPAs and everything else is uncool to them.
For one of my clients projects it started out in what seemed like a simple crud app and so I did the few reactive changes in pure java script. The thing is: requirements changed and now after a while I couldn't get around adding VueJS simply because the reactive changes kept piling up.
Even though the HN sentiment seems to be that all "modern" frameworks are just huge piles of code that you add to your project without understanding how any of this works, my personal opinion is that using something like nextjs with server side rendering is not all that different from using a server side php framework like laravel. You still generate the same html unless you need reactive changes and when you do, you are happy to have chosen that. And to play a bit the devil's advocate: Unless you write your own webserver and template rendering engine you are already using a bunch of code you don't really understand.