I don't think that we can really appreciate literary genius outwith out own - high level - language ability. The field of "comparative literature" is, in this sense, somewhat bogus.
As an historical example; the greatness of Shakespeare was discovered by German critics of the 1700s, and the British learned from them; but I don't think the Germans were really appreciating Shakespeare, because they didn't "get" the poetry.
At any rate, the main reason the German critics appreciated Shakespeare was that they regarded him as a kind of primitive natural genius - a high level sort of idiot savant who spontaneously expressed the folk soul of his race.
This evaluation is essentially false; but it is exactly the kind of mistake made by people who go beyond their linguistic competence. It was the kind of error that made an extremely high European (and American) reputation for the Ossian writings of James Macpherson.
In essence, Comp Lit entails a type of "projection" - of reading-into the author what is wanted to be found there.
Of course this sort of misunderstanding can be valuable in various ways - it can even be fuel for the work of a genius (creative misreading is a real thing).
Yet there is an ineradicable problem when people try to discuss and rank world historical greatness across languages and cultures; and pretend to be able objectively to compare (say) Homer, Virgil, Dante, Shakespeare, Goethe, and Tolstoy...
A few people may have the linguistic ability genuinely to attempt this; but it is not likely that these same individuals also have the needful literary capacity. And yet there are reams of comparative writings on these authors.
Translations are at best re-creations - especially when it comes to poetry; and that isn't the same thing as the original.
The classical tradition of music does, within limits, seem to be more naturally and spontaneously international than this.
It is, at least, possible genuinely to appreciate and validly to compare the European (and Russian) composers back into the Renaissance. So it is quite normal and effortless to appreciate and compare Monteverdi, Purcell, Bach, Beethoven, Liszt, Debussy, and Tchaikovsky.
The limit of valid comparison is more at the level of musicality and experience/ knowledge - rather than a problem with the language of music.
This is presumably why there has been no such thing as "comparative music" which is analogous to "comparative literature" - Comp Mus is too easy and obvious and valid to require an academic apparatus.
But if "the language of music" is far more international and cross-cultural, then it is also much less of a language - if indeed it is a language at all.
We cannot really express what it is about music that it says - whereas we can (to a significant extent) summarize writing by other writing, words being the major medium of communication.
But we cannot summarize music by other music (or by writing); we cannot "translate" a piece of music!
So, to the degree that music is international it seems to achieve this by its being non-propositional - by music being "an aesthetic experience" (or, at least, an emotional manipulator) rather than a meaning-carrying medium.
Therefore; Comp Lit is a kind of semi-deliberate self-delusion!
More a matter of reading-into, than of reading.
But an activity that can be personally fruitful, a source of fuel and direction for personal development; and there is plenty of genuinely interesting stuff to think and say about such comparisons, and the process and quality of translation.
However, Comp Mus is of interest only to specialized (mostly professional and paid!) musicologists and historians - most music lovers will go direct to the music, and appreciate it (or not), without any demand for an interpretative apparatus.
It is just Too Easy to be interesting!
A case of what you gain on the swings, you lose on the roundabouts?