How can i get my series x to download disc games faster?

The fact that you paid for gigabit Internet has absolutely no bearing on how much band with different places are willing to assign you. Gigabit Internet is intended for a family of four who are heavy users.

In my experience Xbox is willing to give, at times that are not heavy load, as much as 250 Mb per second which translates to approximately 30MB per second so it sounds like you’re right in the window. Almost no one will provide you with a gigabit of bandwidth for downloading files or games or anything else. Any outside speed tests you run are to local servers who are not tapped with how much bandwidth they can give you because it’s such a short engagement, and that would defeat the purpose.

The speeds they are willing to give you will download nearly any game inside of an hour

Hi, TRY Using A ETHERNET CABLE OR MOVE YOUR XBOX NEXT TO UR WIFI ETHERNET CABLE 4 BEST SPEEDS :-D

If you are installing from disc, doing the steps above won't make any difference. Those steps will only work if you are downloading the game from the Xbox store. Even that is not guaranteed to work.

Internet downloads can be effected by so many variables that its almost impossible to work out where the problem is, all you can do is make sure its not on your end and then live with it.

It could be that one of the many steps that it takes to get to Microsoft has high traffic, it could be that Microsoft themselves were experiencing high traffic, heck it could be your own provider throttling your connection due to high traffic.

As someone mentioned above, speed tests are almost meaningless as it shows your absolute best download/upload speeds, real world download speeds are rarely ever that good.

Consider testing your Internet connection speed on Teste de Velocidade by Speedtest.net