I’m a bit late, but Atom has “activation-hooks”, which delay loading of packages until they are actually used, or their declared language is used. It’s totally up to the package developer to add these, but it means that the issue isn’t quite as important as you might first believe.
For example, if you have a bunch of Haskell IDE packages (for whatever reason), they’ll only load if you open a Haskell file. If you never open that kind of file, those packages will never load. Similarly, the
latex package will only load when you first open a
.tex file, or run one of it’s commands.
I don’t know exactly what impact this has on load times, but it’s probably relatively minor.