I use Spacemacs (and I like it). For people who switched over to Doom Emacs, I like asking them why did they switch over? What were your reasons?
However, having experienced Evil, Magit, general.el etc. there was no way back. For a while I used my own Emacs configuration that emulated many parts of Spacemacs, but was far more stable.
However, maintaining my own configuration became a bit of a drag. Every time you need another package, you have to figure out how it works and how it can be integrated nicely with Evil/general.el, etc. So, one day I decided to try Doom and I haven't really looked back. It has many of the perks of Spacemacs (sane defaults, space-driven shortcuts), but has been very solid and stable.
When I saw Doom Emacs though I was kind of skeptical at first (this was about 5 years ago), it seemed to have a lot less batteries included, but I gave it chance anyway, longing after the understanding I got when I wrote my own config. I've been entirely happy daily driving it since. Doom Emacs just seems to have a different philosophy than Spacemacs, it's more like a really well designed configuration framework for emacs on which there are nice layers on top instead of the more monolithic Spacemacs approach. I can easily configure it to my needs, write my own custom modules, and hack on it. It really does a sane job updating and managing the packages, something I would waste too much time on with Spacemacs. So to me is that it seems lower level and better software, yet I still get the preconfigured functionality that allows me to quickly go take an emacs install from zero to hero in a matter of minutes. And did I mention? It's fast.
I'm coming from Vim, so having evil-mode as a first-class integration is nice too.