Buckling springs are always noisy (you can reduce but not eliminate the noise by putting vibration damping materials inside the springs). "Clicky" switches like Cherry MX Blues are always noisy. Other key switches are much quieter, and most of the noise comes from operator error. You're not supposed to press them all the way down like a membrane switch. The operating point of mechanical key switches is near the middle of the travel. If you press too hard they'll bottom out and make a lot more noise, as well as tiring your fingers more. If you're prone to doing this by accident you can fit soft o-rings around the keycap stem to cushion the end of the stroke.

Man, it's a good thing nobody else is working there! /s

They still make annoying noises over Skype calls too. Have to tell one of the remotes on my team to mute often.

Who cares the 20 people around me can't concentrate if I can type 5 WPM faster!!

Yet another reason not to force multiple people into a single room.

Not all of them.

at least a monitor though..

I could never do that. I use 3 monitors (if you count the laptop) and I'm way more productive with it. I have low-priority windows that I need to have opened (a terminal, a console log with 3 tabs of its own, simulator window) and that is a mess to handle if I have to actually switch between them. Virtual desktops help a bit but still cause a little strain every time I have to switch from one context (development or checking the source) to another (testing a mobile app and checking the log).

I did that as well! The outcome was an improved way of working.

Single data point here too.

Personally I find great to have a full screen editor/ide without floating file list and symbols one one monitor and documentation/shell on the second. When you look at one you are not interested in the other so I would not call it multitasking but easier process switching.

People who keep the mail client open should try notifications: events versus polling is much more efficient for low clock human beings.