Let me adjust a little bit: front end web dev is a quagmire. If you want to get involved with web dev, start on the back end. If you move to the front end later, it will be with more systems understanding which will be useful.
I’ll say something even more extreme: before getting involved with web front ends, work on some video games with game devs. The know how to make interfaces responsive, unlike most of the slow crap you see on the web. If you can make front ends that are capable and fast, you will be a god among devs.
When’s the last time you saw a video game that launches in under 100 milliseconds? I bet it was a game written for the web.
At it’s best, the web is very fast.
What web games are you playing? Do you count the time it takes to load the web page? I can’t think of a single game that loads so fast, web or otherwise. agar.io is super slow and bloated, hanab.cards takes about half a second to make a room, candybox2.github.io comes close but the network tab reports 128 ms to download the javascript.