All these booths were originally put in place and maintained by the Royal Swedish Televerket, who also had one of the coolest company logos of all time.
Televerket's logo aka "The Crab"
Nowadays the Swedish state have sold Televerket and it has transformed into the public Telia company.
So, what about the anachronistic installation at the Microsoft office?
It is actually a booth retrofitted by Telia and equipped with Microsoft Teams telephony that is currently available from Telia. The top part of the booth is green = available in the photo above, and when someone gets on the Microsoft Teams phone in the booth the top part will shift to red = busy. Also, the glass windows will be changed to frosted for greater privacy when in a call. The booth is built to get people to test telephony through Microsoft Teams and it also illustrates the connection between old style communications and modern solutions.
If you want to test the booth IRL (AFK) there is an opportunity at the Swedish TechDays which will be held in Kista on October 22-24.
An article in Swedish about the booth is found here: Gammal telefonkiosk ska demonstrera modern telefoni