This interview they did last year stirred up a lot of negativity toward the band, and I think some of the skepticism is justified. Is "transcendental black metal" a real thing? Should it matter? Are concepts and intentions such as these important for listeners to know before they listen to Liturgy?
Rejections and affirmations aside, Liturgy does bring some different ideas to the style. For one, there's a lot more syncopation and major chords in their songs. Though I would never call the music "sunny," it's definitely a noticeably lighter side of black metal. Seems like an appropriate message to convey while wearing a white robe.