I've also seen this mentioned on Reddit and unfortunately it seems to be accurate (the site you link to looks a bit sketchy though).
The music of hers that I like is great music and if she was influenced by other songs then that's mostly alright I think.
The couple of songs that are more copies/ripoffs than just "influenced by" do irk me, but from what I saw last time I looked into this none of my favourites were straight ripoffs.
Cowboy Bebop had a really good soundtrack, but on a quick google I couldn't find anything that noteworthy that she's done besides that. What are you referring to?
Interesting. I dont know much about her but i love her scores. GITS (Inner Universe; Rise) and Noir (canta per me; salva nos) are still in my playlists after 20ish years.