Not really sure what low end FOSS editors you are referring to? Textmate?. The Monaco editor predated vscode by 4 years and it was an attempt to build a browser-based texteditor as a take at cloud9 which people thought was gonna be the “future of cloud development”. Vscode happened after Atom (which was not low end) made electron apps viable and cloud9 turned out not to be the future. Both were an attempt at SublimeText (which was not FOSS). SublimeText itself was a cross platform alternative for textmate.

The FOSS text editor space was always crowded between vim and emacs. FOSS alternatives would get measured against these 2 behemoths and it was a tall order to compete against. Now FOSS IDEs were a different story.

Java, C#, and C++ had many sophisticated and advanced IDEs, some FOSS some not. However, PHP, Python, Ruby, and JavaScript were quickly gaining huge mindshare and those developers didn’t want to install Visual Studio, Eclipse, NetBeans, or IntelliJ. It’s a tough proposition to tell a Ruby dev to install Java, then install Eclipse, then install an extension, then learn Eclipse nonesense just to edit your Ruby files vs “just open SublimeText and edit your files”. Most of what those developers wanted was just syntax highlighting and basic directory navigation to begin with. Atom/vscode were an attempt at SublimeText alternative. VScode was objectively better than Atom and TypeScript was also objectively better than CoffeeScript.