As @BlackJack mentioned, there are many text fields in Roon where you can use import settings to tell Roon “when there’s metadata in my file tags and Roon also retrieved metadata, prefer the text from my file tags”, but there’s no way to just turn off all Roon metadata, since there are some fields where the data can only come from Roon.
In Roon, artists and composers are not pieces of text that live in your file tags – they’re actual “objects” tracked in the Roon database, which allows Roon to organize your music in ways that aren’t possible with file tags.
For example, Roon can support multiple artists with the same name (like Bill Evans vs Bill Evans). Roon can also recognize multiple spellings of the same artist, and link them all link back to the same person (for example if your Tchaikovsky recordings from different countries spell the composer’s name differently.)
Roon is designed to organize your collection in more powerful ways than are possible with just file tags. You’ll have to decide whether that works for how you organize your collection.
These docs are a little outdated 
but there’s some more information about this here and here.
If you’re talking about the album browser, both of these options should be available.