Yes, in general that principle holds, but you should also be aware that if you have had a full score layout open during an editing session, Dorico maintains that layout even when you’re not looking at it so that when you switch back to the full score, it’s quicker to switch back because the layout has been kept up-to-date with all of the edits made since you last looked at it.
If you work on e.g. a “focus layout” that contains just one flow, then a good way to make sure things are as fast as possible is to have only one tab open, and one window too, and make sure the single tab in the single window is showing the layout you’re interested in. Then save, close, and re-open the project: now only the layout that’s shown will be kept up-to-date by Dorico, and that may be faster.
You may also find that galley view is faster than page view, and that switching off View > Bar Numbers makes things a bit faster still.
The team has lots of potential strategies to continue to improve the responsiveness of the software as projects get larger, and indeed the 1.2.10 update includes a number of such improvements, so I hope in the future all of these kinds of mitigations will cease to be necessary.