How to limit Xbox App download speed ?

I would like to limit Xbox App download speed because they literally used all available bandwidth. I tried to limit from Delivery Optimization advanced options with Absolute bandwidth set to 0.5 Mbps for both background and foreground download but nothing change, the app still use full bandwidth.

I don't know if this still works as it is an old thread, and I found it in Reddit of all places. First time I've ever found much of any benefit there. It seems this guy wanted the same thing as you and found it was tied to the store which in turn is tied to Windows update. It might be worth a shot to try his solution.
Here's the reddit discussion Here's the setting he changed that also affected game download bandwidth. How To Limit Windows Update Download Speed Using This Hidden Setting

There are also third party apps that you can use to accomplish it, like Netlimiter, if this doesn't work for you..

Most of the recent Reddit comments point to W11 Xbox App ignoring the Delivery Optimization limits.
Including this thread on MS Answers.

garlin said:

Most of the recent Reddit comments point to W11 Xbox App ignoring the Delivery Optimization limits.
Including this thread on MS Answers.

Click to expand...

Yes the Xbox App literally ignoring Delivery Optimization limits. NetLimiter worth a try.