Sure. I think all the info you need is in this screenshot [0].

According to "Matt" [1], It scans the folders related to Chrome. Please do not worry as your data wouldn't be effected by the clean up tool. .. I think reality speaks for itself. My Steam Library just isn't related to Chrome.

[0] https://imgur.com/QtcSXY9

[1] https://support.google.com/chrome/forum/AAAAP1KN0B0T8qnffV5g...