Slow download speeds for small downloads ONLY.

The time it took me to write this (about 10-15min) my 1.5gb update has moved 2%. 😂😂😂

If your download speeds are always low and other devices you use are slow too then you might want to contact your internet provider. If it is only the xbox, it may be because there is a larger amount of users logging on due to recent events in the world.
I remember when I would download at night my speeds would drop a little bit. Now sometimes I can download at a couple hundred kbps. Only the xbox's download speed would be slow and only at night.

Yeah it does,only last night I was downloading something while using Netflix.

It will slow the download a little,obviously it depends on your download speed as to how much.

Yes, any games or apps downloaded through the store are capped at the same speed showing in the speed test using Edge.

While I also get less than optimal speeds when I speed test through Edge, my Marketplace downloads are consistent with my internet speed (granted, I "only" have 100Mbit, and due to the distance from the DSLAM I "only" get 70-80Mbit download speed).

So are the actual marketplace downloads when you download a game or an app equally slow?

No dice. I only recently tried using background downloading as a workaround--I had the same slow download speeds before having background downloads. I've never activated cloud storage.