I am entitled to my own opinion on iTunes, not sure how that could be interpreted into slagging you off. I am also more than qualified to disscuss the functionality of iTunes, see:
https://www.dbpoweramp.com/about.html
Some major features which you might rely on (such as Genius playlists), track ratings, we invented them first (over 25 years ago)...
I could write an article 20 pages long on the areas it gets things wrong (this multiple Artists is one area, where they seriously impact the market as a whole because as you are finding. We are expected by some to target the lowest common denominator, which in this instance is iTunes, by default). Admittedly though it gets some things very right.
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Convert one album to test the results before letting it loose on your whole collection.