You didn't address my last points but I'll still address this comment.
> this very sentence sounds absurd
Which part? "hydration", "improve the initial load times", or "PWAs"?
Let me rephrase if you are confused. It renders a snapshot of the app on the server so when you first load the web app it's rendered already. Then the client picks it up from there. It's completely optional to do this.
> how many websites out there need to work offline?
Are you asking if it's useful to have access to information and entertainment offline? For me the answer is yes.
It depends what you are making, but yes I think you should strive to make things work offline if you can.
Also websites can work offline without CSR. That's not really what this is about.
Hydration is about improving initial load times of CSR. I really don't know how to simplify this further.
> this very sentence sounds absurd
Which part? "hydration", "improve the initial load times", or "PWAs"?
Let me rephrase if you are confused. It renders a snapshot of the app on the server so when you first load the web app it's rendered already. Then the client picks it up from there. It's completely optional to do this.
> how many websites out there need to work offline?
Are you asking if it's useful to have access to information and entertainment offline? For me the answer is yes.
It depends what you are making, but yes I think you should strive to make things work offline if you can.
Also websites can work offline without CSR. That's not really what this is about.
Hydration is about improving initial load times of CSR. I really don't know how to simplify this further.