Yes, the claim is largely true. Adele has never featured another artist on her core studio albums (19, 21, 25, 30). Her work stays almost entirely solo. Why? Her songs are deeply autobiographical—she writes and sings straight from her own life, heartbreaks, and growth. Features would break that raw, personal thread. She’s turned down tons of collabs to protect it, values the album as one uninterrupted story, and still crushes it solo. Pure artistic control and authenticity. That’s part of why she’s so respected with minimal drama.