I think what they’re referring to is being able to get some rolls and ghost notes and things that are subtle parts of a beat or a fill but aren’t the main part of it.

An edrum set is way fun, and a great way to learn the basics and figure out what styles you like etc etc. but unless you get a super-fancy expensive one that has multiple triggers and such, it’s basically one hit = one sound. Whereas on an acoustic drum the way you hit it (angle, force, stick type, head type, drum type, tuning) all change the sound in certain ways. Cymbals, the hi-hat in particular, are super expressive but in electric form usually get limited to one or two sounds.

Don’t worry about it for a long time though, just have fun. I love that there’s tons of drummerless tracks out there so you can play along with songs you know. Do that. Rock the Casbah.