Yes, and every major MPA framework optimizes this away, the same way that SPA approaches support server side rendering so you don't see a literal blank page before the app downloads.
I think GP is talking about solutions like https://turbo.hotwired.dev/, which just paste server-generated HTML into the page instead of passing JSON into a client-side UI framework.
> During rendering, Turbo Drive replaces the current <body> element outright and merges the contents of the <head> element. The JavaScript window and document objects, and the <html> element, persist from one rendering to the next.
Does SSR make React a MPA? If "MPA" limits us to only frameworks that have to do a full browser navigation for every interaction, it's a pointless discussion - "MPA" frameworks have had these sorts of optimizations for a decade+ (Hotwire is the newest, but there was Turbolinks before that and PJAX before that). Sure, I'll agree that React is a better approach than using the 2005 version of a framework, but that's not useful.
Architecturally, you'll still designing your application as though the user is performing a complete navigation, there's just Javascript present to optimize away some of the issues with that approach.
... wut?
Wouldn't that make them 'compile to SPA' frameworks?