The source isn't available and purely business-wise Opera would be fools to create a competitor by releasing it. You or I might make that decision regardless for the public good, "business be damned", but I don't see an investor company doing that.

And who knows if it's actually any good. It was around form the mid-90s to 2013, and I'm betting the "wtf per minute" is pretty high. Probably better invest in Servo or that thing the SerenityOS people are working on.