EDIT: To expand on this, why is modern software slow? The reason is because people, thinking their code isn't a bottle neck or performance doesn't matter but adherence to the right abstractions is, they write slow code and call backs thinking everything just happens immediately, with layers of abstractions, and those little innocent steps add up when every piece of code written today is written with that same neglect. The call backs runs slowly, queues fill, promises hang, and so-on and on we go.
So sure, may be your code doesn't seem like it needs to run at 60fps. But when everything I do on a computer is written like it will be run every 10 seconds, it definitely will be noticeable. That's because I don't just run your program or look at your website, I look at 10 of them or even more. If I average all of those per time, then may be your code should in fact be able to run at 1Hz or so or I will start to notice.
People of course were right not to teach new devs not to over-optimize immediately, but the culture has swung so far in the other direction, especially since you all seem to love complexity so much, you've managed to yes make computers that can calculate pi faster than a super computer from the 70s crawl when it renders and handles an editable textbox. There has to be a move back in the other direction, you guys need to give a shit about performance, at least a little.
while (command != 'quit') {
command = readline()
handle(command)
}