His point is that probably just GTA5 has sold more copies in 5 years than all Valve games combined (a quick check of the most popular ones, HL 1/2, L4D 1/2, Portal 1/2 reaches about 30 mils), so that number of employees is justified.
There is no denying Valve does great with the number of people it has, but of all the badly managed companies they could be compared to, Rockstar really it is not a good example...
Rockstar is certainly doing well profit-wise in the industry, but I think Valve still compares favorably productivity-wise.
In the last few years, Valve has developed multiple new pieces of hardware with software support; the Steam Controller, Steam Link, and HTC Vive. They've also developed and supported a new platform, SteamOS, and rolled out hardware with manufacturing partners. Besides this, the Steam platform has added live-streaming (like twitch), family sharing, big picture mode, the VR UI, and other features. They were also involved in the development of the graphics API Vulkan, which they need for their Linux-based SteamOS to become a better platform.
These are just what I can think of off the top of my head and don't even explicitly involve any games (though they released a collection of 11 small experiences for VR as well).
I only wish I could give you multiple upvotes. Valve has been huge for Linux gaming and if I understand correctly, were a major factor in the push for Vulkan. They can indeed Take My Money.
Most of the stuff Valve is selling nowadays are addons to already existing games.
Interesting thought experiment: Break the sales for DOTA and TF2 into ~$50 increments and compare that number against total sales for the last two GTA's put together. I suspect Valve will beat them at least twice over.
Also:
http://www.gamespot.com/articles/gta-5s-online-mode-has-gene...
There is no denying Valve does great with the number of people it has, but of all the badly managed companies they could be compared to, Rockstar really it is not a good example...