I was a long term user of Brackets (since 0.14!) before I switched to VS Code sometime in 2016 because it just worked so well with Typescript. I tried to switch to Atom several times but could never get over the slugginess of it compared to the other two editors.
There were other issues too, the way they handed project folders, intellisense for Scala, but the slugginess was the main issue. I often had to debug large JSON files and while Brackets and VS Code would open them almost immediately, Atom would take several tens of seconds.
Also, personal issue was that I didn't like the default keybindings they had for macOS. I don't remember what they are anymore but there were lots of what I thought should've been obvious defaults that weren't.