Sibelius is named after a composer. Dorico is named after an engraver, isn’t it?
Which is interesting, because Dorico keeps the two worlds separate: composing and engraving, with a very clear boundary in the tabs (write/engrave). When I started with Dorico, having come from both Sibelius and MuseScore, I found it maddening that in Dorico I couldn't easily perfect the placement of text, hairpins, slurs, visually, while writing, as you can in Sibelius. However I began to embrace the fact that write mode truly is for writing, and when composing there really is no need to perfect visual engraving details – in fact it's just a distraction. Just like if I was writing a book in a word processor, my focus would be on the words and not the fonts or spacing etc.
Not necessarily what you are saying, but to that point, I actually find Dorico to be more enjoyable for writing - and I personally don't do much engraving, but the times I have used the engrave mode in Dorico, I kinda hate it.
My point being, Dorico in my personal experience actually feels like a better writing tool than engraving tool, but professional engravers and publishers might have a different opinion there.
One thing I know for sure, times I've re-opened Sibelius since then, I now find it maddening when I go to select notes or move compositional things around, it's also easy to accidentally adjust bar sizes, system distances, hairpin sizes—visual engraving stuff—and if you're not paying attention things can start to look rather inconsistent. I enjoy that Dorico frees me up to not think about these things when writing - it handles all the back-end consistency for me and makes stuff like condensing an absolute breeze.
With popovers, shortcuts, and the way the input mode / caret so elegantly handles math for me, I find I can write at a blazing speed. Of course that's not to say someone can't write fast in Sibelius – I had a composition teacher who flies through Sibelius in the blink of an eye. I guess what you get used to and develop muscle memory for. But I really enjoy that Dorico allows me to focus on just writing plain and simple.
That said, I do agree the D. developers have a stubborn air about them. I've made suggestions on their forum many times which are met with skepticism, "why would you want to do that?" or some roundabout explanation how the team has already decided on something and will not change it, which I think is funny if several people find something confusing and keep asking about... There are some UI suggestions I've made and the general response I've gotten is - deal with it, or "here's a complicated workaround..."
But on the other hand and to be fair, considering the short lifetime of the product, their pace of development and updates outshines Sibelius by far. Every update is rather comprehensive, not just a couple bug fixes, which I appreciate. And there are a few things I've noticed added lately which they said previously "they will never do" – one example, they were flat out refusing to allow clefs with an 8vb or 8va to affect playback, because they considered this to be wrong; but in a recent release, you can now toggle this in preferences. So they listen, just with a little bit of a 'tude I guess.