Digital work is faster in the sense that its faster to get to a desired result, because a digital file is malleable, undo-able, and multi-dimensional in a way that a piece of paper can't compete head-to-head with. It can also do a lot of things that physical work could never do, without post-production. 

For example, with older Disney work, you're seeing a lot of photography tricks, like painting on multiple sheets of glass and then filming in an astronomically expensive, custom camera rig that mechanically produces parallax effects. Or, that famously magical "fluid motion" produced by rotoscoping-- painting over film of a live subject. With modern animation, all of those camera crews and other support staff for physical, mechanical magic tricks can be performed by legions of individual artists with modest desktop workstations. I'm just spitballing here, I'm not an animation expert. 

I do know about comic book art, and what I see happening in the industry is this: There used to be pencillers, inkers, and colorists-- in modern comics, you'll often see a single artist doing all of those jobs, producing complete, finished pieces ready to be published. You would think that one person doing three jobs would be a real challenge in a medium that is published monthly, but that's not what I'm seeing. The modern generation of digital comic artists has single artists who are able to produce complete art for multiple monthly titles, and the work itself is fantastic-- in fact leagues ahead of anything we could have imagined in the 80s/90s.

This is what I'm trying to figure out-- how to most efficiently utilize the tools available to produce quality work as efficiently as possible. 

Disney also used to re-use a ton of animation sequences, in ways that no studio today would get away with: