Onivim's vim emulation is great.. Because it's literally using libvim. It's also very snappy. But thats where the advantages end.
I'm surprised to hear this take. I've been a Doom Emacs user for a while, and while it was a bit more elbow grease to get it running on OSX, it was generally worth it for the speed/flexibility...
until
I ran into a non-trivially large Terraform code base. Slowed.to.a.crawl.
On the other hand, even with multiple plugins, VSCode was(and continues to be) very snappy. Nearly instantaneous search and motion.
I'm sure at least one time spacemacs was partly to blame (aka ALL THE THINGS activated/installed) - but it's definitely a difference in "feel" where (Neo)Vim feels closer to vi, and emacs feel closer to vs code/Atom.
Did you ever spend any time debugging what the issue was by any chance? Even with lsp enabled, I wasn't very impressed with any of the features it gave me (emacs or even in vscode)
Well if you are used to IDEs that also had that kind of lag...