Steam slow in download?

I've always had the problem that on Steam, on the Internet, on Origin, Uplay etc. My download was slow (0.1 to 4 MB / s at the most). I always thought this was my internet (Wi-Fi). Then I downloaded something from the MS Store for the first time. It says 20 MB / s. According to speedtest.org I have a download of 21.28 MB / s and an upload of 12.89 MB / s. Does anyone know why this is? I have the same problem on my laptop, but I don't know if it loads faster in the MS Store.

I've already tried to set another download server on Steam and (without success) looked in the browser settings.

Notes: I do not confuse MB / s and Mbit / s. // It's not the hard drive.

But you mix up MB / s and Mbit / s.

The Ms Store and also Speedtest give you Mbits / s. Steam but Mbytes / s

I've mixed it up in the MS Store, that's right, but at speedtest.org it's MB / s, because I'm still open. Nevertheless, it is 21.28 MB / s

Bandwidth is always given in bits, which is also on your speedtest.org page. https://www.speedtest.org/understanding-a-speed-test/

There's no speed test with megabytes / s