Well why do people write music, write poetry, draw painting etc
To communicate and to express themselves and hopefully express themselves in a way that people find it interesting and entertaining. The same reason why I write essays critiquing it.
Music is ultimately subjective. There is no objective good or bad in music. As George Starostin wrote in his essay, the only objectivity in music is via subjective standards.
So what's the point of music reviews if everything is subjective?
1. Objective description of a work so that people learn about the craft behind the work people like or dislike. Even if you disagree 100% of my values, if I say this production removes the transient from the instruments, or this music sucks because it isn't in sonata form you may think that is a good thing, or The Beatles write great melodies because they create melodic lines with an antecedent and consequence etc you may think my values of rating those thing that way as wrong but if what I was saying is objectively truthful, you'll learn more about the mechanism behind the music irrespective whether you agree with me or not.
2. Personal expression from the writer is interesting in of itself. Why do people read George Starostin or Mark Prindle opinion of music when their opinion is no more objectively correct then anyone else. This is because music filtered through their personality is interesting and entertaining in of itself. Music reviews is less about the music itself and more about the personality behind the people writing it.
I'll argue with Pugeye or BD or Tony V not because I'm trying to convince them to agree with me (when I write about music, I do not try to persuade at all, I'm completely aware that nothing I'll say will change their mind). I just do it so I can try to elicit their values of music while at the same time express my own.
Now if you think all of this is garbage. That's your choice but really, I'm not doing anything different to any other music critic either amateur or professional. Just writing about music but reflected by my own values and my own personal knowledge in music. I'm not too sure why you'll be against my opinion but be perfectly fine with reading music reviews in general.