Sorry but whats wrong with terms like not relevant or redundant? Aren't they self-explanatory? Not relevant means without any importance for musical history and redundant means superfluous (People had better spent time for something useful than recording boring music). What about the freedom of speech in this Forum?
No, they are not self-explanatory. However, you have offered definitions....finally.
You suggest that to be "relevant" music has to have "importance for musical history". That would suggest that the only composers whose music is "relevant" are those who are generally recognised as among the "great composers" or those who have in some way shaped the course of musical development through their influence on others.
If we accept this then literally hundreds of composers who wrote music within an idiom conventional to their particular time would be "condemned" as "irrelevant". Yet many of these composers wrote music which is admired by many of the members of this forum. It is certainly acceptable to find nothing individual or innovative in their music. It is equally acceptable to say so.
But you also use the word "redundant", meaning "superfluous" and "boring". Superfluous suggests that the music should not have been written or listened to. That is a frankly astonishing assertion! You sweep aside the musical tastes and judgment of many of our members. That is unacceptable.
You refer to "freedom of speech" on thiis forum. There is no unfettered freedom of speech. There never has been. We expect members to respect the views, opinions and tastes of others and to conduct discussion in a decorous, ie polite and courteous fashion.
Like every other music lover I have musical "preferences". I find it difficult to listen attentively to a Mozart piano concerto. That however does not render Mozart's music "irrelevant" or "redundant". Mozart was, unquestionably, "a great composer". I would expect (and have plenty of experience of) the baffled incomprehension of others when I express my aversion to a Mozart piano concerto. There are a handful of other, very well-known and well-loved composers whose music holds no great appeal to me but I would certainly not dismiss their music for that reason.
This forum is populated by people who prefer to discuss the music they like and to attempt to share their musical enthusiasms rather than to persistently and continuously rubbish the music of composers under discussion.
The use of the words "relevant" (as usually in "not relevant") or "redundant" has become tedious in the extreme. In my capacity as an administrator I have already said this explicitly. If you do not "like" my attitude then you can reach your own inevitable conclusions.