No. She's a musical singer and while she clearly has classical training, it doesn't make her an opera singer. Musicals are often sung with microphones while operas do absolutely not have microphones. The signers have to have voice control and stamina to reach the third balcony listeners in the back corner.

(Phantom of the Opera is a musical that was composed to her voice in particular, bc she was married to Andrew Lloyd Webber at the time.)