Rituals are applied philosophy. When you say “don’t reduce greatly philosophical Dharma to rituals” & other such tripe, you might as well say, “don’t reduce beautiful theoretical physics to applications”. You won’t get anywhere with such a naive attitude.
Even when śāstras critique rituals, read it carefully. It’s not a dysphemism to target mechanical performance but a genuine critique. A text critiquing ritual system X is actually promoting ritual system Y or contemplative praxis (inner ritual) Z. There’s no escape from action.
The Vidyās & Upāsanas of the Upaniṣads are all rituals. Śam̐kara’s commentary, on the sūtras of the Brahmasūtra pertaining to these Vidyās, discusses the issues & validity of combining multiple Vidyās in multiple Vedic texts. What does this sound like?
If you are astute, this would remind you of Mīmāmsaka discussion of Śrauta rituals. No mainstream Ācārya has ever suggested pure theory in lieu of practice for ordinary people.
The reason I share a lot of the doctrine/“theory” here is because it provides the best motivation for high-quality praxis for both teachers & students of a tradition, not because such doctrines are ends in themselves. Ritual is the culmination, the real deal.