As someone who switched from Atom to VSCode some time ago, I'm yet to find anything that VSCode doesn't have – are there any notable examples where Atom is ahead of the curve or is it just that it has more plugins?
I switched from Atom to VSCode a while ago, but I still miss a very good git extension (which I can't find now, sorry) which put timeline marks by change size in the bottom of the editor window to allow easily viewing diffs. The best regex railroad viewer extension I found was also much better than in VSCode. As well, VSCode seems to have some bad UI paradigms, for example, using Prettier, syntax fails pile up obnoxiously. I suspect all these differences are because Atom had better UI access for extension developers. I'd switch back to Atom but I found it had a few glitches and VSCode has stronger features such as debugging and code comprehension built in.