[jaldhar]

We know more about changes at the elite level because the archaeological and literary evidence favors it and yes there was a significant shift in patronage but the Bhakti movements grew at the popular level too.

Buddhism in that time and place was entirely monastic. If you were a layman you could support the sangha but you kept your existing dharmic commitments. You were not exclusively “Buddhist” unless you became a monk. Also it seems the condition of nuns had become rather bad.

Shaivism etc. by contrast had a complete path that addressed worldly concerns as well as liberation, for householders as well as ascetics and accessible to men and women of all castes.

[rg111]

There were millions of Buddhist householders. They not only supported the monks, but also practised Buddhism.

Buddha told Ananda that hundreds of his householder disciples attained Nirvana.

[jaldhar]

What does it mean to practice Buddhism if not a monk? Can you point to specific activities (as opposed to general ethical principles) that must be performed by a layman? Buddhism did develop such things but later than the period under discussion and outside India.

Shaivism etc. (and for that matter Jainism) had clear and specific codes of conduct for grhastha disciples.

Sutras continued to be produced long after Shakyamunis lifetime and some anachronistically ascribe later ideas to early figures.