Praise your friend for those Bose 301s that he enjoys and is proud of! Or... you could try to educate him about why his speakers are just so wrong..
The praising or the educate is both inadequate from my perspective.
If the "friend" is
enjoying listening to music regularly, in an attentive manner, then that is all that matter. Their is nothing intrinsic wrong in his Bose 301s that will prevent him or anyone else to enjoy listening to music on those speakers.
Speakers, as opposed to electronics, where we know and have known for a very long time, what works or does not work and can back it up with simple measurements, are not so easy to characterize, if only but not only, because they have to interplay with a room that is even more difficult to get meaningful measurements from.
At the end we get something compromised and have to make choices that align with our preferences. Having a dedicated room where one can set the speakers and the listening position to allow our preferred experience, is a huge advantage, but is not a guarantee of success either. Success is a very general concept, as we may not be after the same kind of success. to me success is when the music is engaging, hearing/feeling the emotion it is supposed to carry. For other success is a flat sound or a deep soundstage or deep bass. every body is chasing a different target. Until the perfect speaker comes to market, we all have to live with a compromise that meets our goal and let us
enjoy listening to music.
If that friend is referring to a specific issue he would like to fix and we think the issue it directly cause by his speakers, after we heard it for our self, then it might be the time to guide him into trying a different speaker that might fix the specific issue in his set up, that this friend is complaining about.
@CurtR this post is not specifically directed at your post, I just quoted your comment for context, I am just expressing my Opinion as it relates to excessively relying on speaker measurements as we would to electronic measurement, when speaker measurement and what we hear where they are playing, at this point in time, are extremely subject to interpretations that may or may not match with what we are aiming at as individual in the comfort of our home.
If you like what you hear, you are golden, don't worry and enjoy the music.