It's said that their old UI toolkit called "Quick" is completely dependent on Presto so it's incompatible with Chromium.
That doesn't mean they can't reimplement the interface, which they obviously chose not to do.
Right now, Qt5/WebKit-based Otter Browser (still in alpha stage) looks more like old Opera than the new Opera after 5 major versions. And it's a 1-man hobby project.
By the time Otter is a year old (like new Opera next month) it will surely have more than half the features of old Opera.
Months ago I couldn't see any difference between new Opera and the oldest releases of Chrome. I still can't see any difference.
Nowadays I only visit these forums and the blogs for educational/entertainment purposes, especially now that they have dropped support for FreeBSD and it's become a dead end anyway.