"The server also holds on to some state for each client"

If this is how Blazor is architected. Then I have no interests in using this and really anyone doing any type of web development shouldn't bother with this. Internal apps eventually need to be used externally. This is a time bomb waiting to explode on the users and the developers.

I use VueJS with Asp.net Core with multi-page single load architecture. Meaning once a page is loaded all other data is loaded through ajax. But the app is made of multiple pages. Over 10 years of being a web developer has brought me to this setup. Client UI state should stay on the client. All other state should be saved to the server. All communication should be stateless.