in my thinking, the question is -- will a very good speaker with a very good amp be inferior to a pretty good powered speaker.
While the powered speaker will have an excellent match between the speaker and its amp, will the advantage of having that matchup outweigh the "better" quality of the very good separates?
The audiophile marketplace seems still to prefer the separates, but at this point, it is up to the buyer’s listening preferences.
We have a member here that contended that his powered speakers were better than any "cost-no-object" separates. While his claim did not change my thinking, I was glad for him that he was so happy with his rig. However, I vowed to doubt any further opinions he would post.
Now if Wilson Audio were to ask Nelson Pass to design amps for a powered speaker system, I would be happy to consider such a system might be "better" than separates. But this hasn’t happened (yet?), And current powered speaker offerings are not convincing (to me).