How many thousands have big offices just to do powerpoints ?

This prima facie logical fallacy of "here's a nice £0 you can multiply anything with" has been addressed long ago:

> At this point, it’s pretty common for people to try to confuse things by saying, “aha! But Linux is FREE!” OK. First of all, when an economist considers price, they consider the total price, including some intangible things like the time it takes to set up, reeducate everyone, and convert existing processes. All the things that we like to call “total cost of ownership.”

https://www.joelonsoftware.com/2002/06/12/strategy-letter-v/