Performance is critical to the success of any application framework. If operations are slow, pages render slow, interactions are slow, there will be no adoption of a framework. Microsoft knows this better than anyone. With Blazor, like any new technology, there are always issues that come up with a version 1, some of them related to performance. The biggest pushback with Blazor is around the size of the package that includes the .NET Framework and the WebAssembly of the actual application being run. Since WebAssembly is more than a simple HTML page, it includes DLL’s and binaries that are sent from the server to the client, there is a risk of a larger initial payload, which could affect your app if it is a SaaS app on the web. For internal line-of-business apps, payload size is usually not relevant. Microsoft is committed to addressing performance issues in Blazor, from the initial payload size to the overall performance of runtime execution on the client.