It’s quite surprising that in this day and age, that there is still 32-bit software in use. Visual Studio is a prime example. Windows has been 64-bit for quite a while now.
If you look in Task Manager, you’ll probably notice that programs with a (32 bit) after their name are few and far between.
On the screenshot, only one out of 11 is 32-bit and that’s pretty typical. Linux and Mac are probably similar. Here’s a stackexchange question on how to tell if a process is 32 or 64 bit.
In Visual Studio, it’s very easy to switch between 32-bit or 64-bit compile target. Unless I have a real need, I go for 32-bit for programs I write because they are typically not going to need over 4 GB of RAM. And 32-bit code usually runs faster than 64-bit because instructions are typically shorter which means more instructions in the execution cache etc.
However some systems have a lot of code and there are people who want a 64-bit version of Visual Studio. You can read some of their requests here.
I’m still on a Linux laptop BTW. My new cooler has turned up and tomorrow I hope to install it. The Windows screenshot came from my work laptop which I emailed to myself!