Yes. There is key difference between classical practice (topically discerning an exceptional solo from the regular, titular and thus obvious soloist) being fuzzy from pragmatics, and MusicBrainz’ accuracy standard: If you will, anti-alias vs. exacted ID. Stems from classical concept of form traditionally expressed through classifying titles (symphony, sonata, suite, fugue, …) differing from popular tradition where less focus on form leaves no need for classifying (main form: song) but room for poetic reflection (title typically lyrical).
Some well-known examples of solos often specially credited:
Bach: [Many vocal movements with obbligato instrumental solos]
Beethoven: Missa solemnis: IV. Sanctus; Benedictus (Violin solo)
Berlioz: Symphonie funèbre et triomphale: II. Oraison funèbre (Trombone solo)
Schumann, Clara: Piano Concerto: II. Romanze (Cello solo)
Brahms: Piano concerto 2: III. Andante (Cello solo)
Brahms: Violin Concerto: II. Adagio (Oboe solo)
Saint-Saëns: Symphony 3 (Organ solo)
Strauss, Richard: Don Quixote (Viola (, tuba & bass clarinet) solo)
Strauss, Richard: Ein Heldenleben; 3. The Hero’s Companion (Violin solo)
Shostakovich: Piano Concerto 1 (Trumpet solo, verging on double concerto)
Ives: The Unanswered Question (Trumpet solo)
Pettersson: Symphony 16 (Saxophone solo verging on concerto)
Messiaen: Symphony Turangalîla (Ondes Martenot solo)