Could be also AOC getting more popular and hitting the developer mainstream more, hence skewing the percentages more in favor of mainstream tools. The absolute number of devs from "fringe" groups might have stayed constant.
Though VS Code is also getting quite popular in general, so probably that too. It is quite lightweight, just works and setting up new languages is a matter of a few clicks. Honestly the only reason I am not using it (other then not trusting or wanting to support Microsoft), is that the VIM emulation does not feel quite right for me.