Add server-side rendering (via bundleRenderer, as this is what the Vue docs recommend, and apparently the only way it does encapsulation)

templates/VueSpa/Views/Home/Index.cshtml

@@ -2,8 +2,10 @@
     ViewData["Title"] = "Home Page";
 }
 
-<app>Loading...</app>
+<div asp-prerender-module="ClientApp/dist/main-server">
+    <div id='app-root'>Loading...</div>
+</div>
 
 @section scripts {
-    <script src="~/dist/main.js" asp-append-version="true"></script>
+    <script src="~/dist/main-client.js" asp-append-version="true"></script>
 }