@terziyski I can confirm that it is plugged into a USB 3.0 port, tried multiple both directly into the computer and using the stand. 

  @terziyski The adapter is in the same room less than six metres away. It's set to 5gHz so no interference from other 2.4 gHz. It's being used as a hotspot so no association speed to the router (for reference I get about 866 mbps from the router at 5gHz).

Driver version: 1030.22.405.2017

  @Luxianos 

Hi,

Using Wi-Fi cards/adapters (which are predominantly designed to be client devices) as Wi-Fi access points via the "Hotspot" feature provided by the computer's operating system has rarely been a great experience for users who are looking for maximum performance. This Hotspot feature is really more of a gimmick that might come in handy in certain situations. And besides, even those relatively "slow" speeds are sufficient to browse the web, send and receive email or watch videos on Youtube and others, which is likely good enough for most users.

If you want predictable high wireless performance, then better use a dedicated Wi-Fi access point (or Wi-Fi router in access point mode) that you connect via Ethernet cable to the Ethernet port of the computer.

By the way, for comparison, I myself have also tested the Hotspot feature of Windows with three USB Wi-Fi dongles that use chips of the Realtek RTL881x series and got download speeds of about 60 Mbps (RTL8811) and 120 Mbps (RTL8812) on the client device that was connected to this Hotspot.