I didn't downvote the comment (yet), but I understand why many people did: It's incredibly dismissive and wrong! Yes, you should adopt methods for keeping the context so you don't lose it and continue from where you started. I've added plenty of tools to my mental toolbox, and now I work on more complex problems more quickly then before. However, even with good context-keeping skills, protecting a block of time will still 10x your productivity over being interrupted constantly.
Developers don't demand focus time for their own comfort. It's because the focus time is necessary for good work.
1. It tries to address the sympthoms without solving the problem. Building a workflow around the distractions assumes that my time is less important than everybody else's.
2. Programming is hard. The comment suggests that the solution to the overhead caused by context switching is... adding more overhead. How about letting people work in peace instead?
In short: my work is rarely "beads on a string" that can easily be popped off, and to the degree they are, the unit of time is typically hours, not a half hour.