Both are very opinionated frameworks. Basically, they establish a convention for dealing with packages and custom config code, and build from there.
With Spacemacs, the expected default is to use Vim-style editing, with the addition of the Space key (hence the name) to access all of Emacs functionality. It's quite user-friendly and very discoverable. And it's still Emacs, so it offers a lot of customization.
Doom Emacs is a more focused approach, it has a clean set of defaults, and the ability to load lots of optional features. One key difference with Spacemacs is the use of an extra CLI utility to manage things such as package installation and config upgrades. Doom also disables customize-mode, which leads to cleaner configs at the cost of some discoverability.
Personally, I've been using Spacemacs for years, the key shortcuts just make sense to me, and it includes everything I want. I also love the default theme, the documentation is helpful, and the main drawback, long startup times, is minimized because I never exit Emacs.
Let me clarify that Doom Emacs is not "same as Spacemacs, but faster". This is probably one of the biggest misunderstandings about these two Emacs frameworks.
You can end up with a similar feature set using any of the two, and yes, Doom Emacs will probably be a bit faster, but they are not entirely equal. The user experience is different, one easy example is that while using SPC as a leader key is a feature in both, the keymaps are quite different.
My recommendation would be to try them both: they are easy to install, and uninstallation is as simple as removing the Emacs config in your user directory.
With Spacemacs, the expected default is to use Vim-style editing, with the addition of the Space key (hence the name) to access all of Emacs functionality. It's quite user-friendly and very discoverable. And it's still Emacs, so it offers a lot of customization.
Doom Emacs is a more focused approach, it has a clean set of defaults, and the ability to load lots of optional features. One key difference with Spacemacs is the use of an extra CLI utility to manage things such as package installation and config upgrades. Doom also disables customize-mode, which leads to cleaner configs at the cost of some discoverability.
Personally, I've been using Spacemacs for years, the key shortcuts just make sense to me, and it includes everything I want. I also love the default theme, the documentation is helpful, and the main drawback, long startup times, is minimized because I never exit Emacs.