I used lsp-mode for a while and then switched to eglot. The reason was that lsp-mode has quite a lot of dependencies including helm and hydra. This can be inconvenient when you use their alternatives likes the vertico-corfu stack. I didn't want more than one extension of the same type in my configuration. eglot uses native emacs APIs for completions and tooltips. This integrates very well with vertico and corfu.
> Also I wonder: if eglot is now part of Emacs, is there any incentive for the lsp-mode devs to keep working on lsp-mode?
I'm pretty sure that some people will stick to lsp-mode. There are a few builtin extensions which I replaced with more popular external packages (eg: projectile vs project.el). So, I think the lsp-mode devs should keep at it.
lsp-mode does not depend on helm or hydra, or anything else really. There are optional packages that allow it to work better with those systems though.
Lsp mode depends on neither helm, nor hydra. I think there are some utility things that can use helm, but as far as I remember it that didn’t require that helm was set up for anything else and it has never conflicted with anything else I use.
> Also I wonder: if eglot is now part of Emacs, is there any incentive for the lsp-mode devs to keep working on lsp-mode?
I'm pretty sure that some people will stick to lsp-mode. There are a few builtin extensions which I replaced with more popular external packages (eg: projectile vs project.el). So, I think the lsp-mode devs should keep at it.