[Problem/Bug]: DataReader.ReadBytes is slower than WebView1 counterpart

What happened?

Similar to this issue https://github.com/MicrosoftEdge/WebView2Feedback/issues/3486

DataReader.ReadBytes is slower in webview2 compared to webview1.

Reading 1MB of data from disk takes 1855ms in webview2 compared to 7ms in webview1.

Importance

Blocking. My app's basic functions are not working due to this issue.

Runtime Channel

Stable release (WebView2 Runtime)

Runtime Version

No response

SDK Version

No response

Framework

WinUI2/UWP

Operating System

Windows 10

OS Version

No response

Repro steps

var appRootFolder = Windows.Storage.ApplicationData.current.localFolder;
appRootFolder.getFileAsync('dataPath').then(file => {

    Windows.Storage.FileIO.readBufferAsync(file)
   .then((buffer) => {
                                         var timeMs = Date.now()
       const dataReader = Windows.Storage.Streams.DataReader.fromBuffer(buffer);
       const bytes = new Uint8Array(buffer.capacity);
       fileData = dataReader.readBytes(bytes);
       console.log(`>> readBytes took ${Date.now() - timeMs}ms`);

   });
});

Repros in Edge Browser

No, issue does not reproduce in the corresponding Edge version

Regression

No, this never worked

Last working version (if regression)

No response