Does Mount Meru and/or Mount Meru [provisional?] cosmology feature prominently in any areas of the Pali Canon and/or Theraváda Buddhism at large?
Bhagavā arahaṃ sammasāmbuddho:
Svākkhāto yena bhagavatā dhammo / Supaṭipanno yassa bhagavato sāvakasaṅgho
Tammayaṃ bhagavantaṃ sadhammaṃ sasaṅghaṃ / Imehi sakkārehi yathārahaṃ āropitehi abhipūjayāma. (Dedication of Offerings)
此等諸法，法住、法空、法如、法爾，法不離如，法不異如，審諦真實、不顛倒。These many dharmāḥ, the residence of these dharmāḥ, the emptiness of these dharmāḥ, these dharmāḥ self-explain, these dharmāḥ are thus, these dharmāḥ do not depart from their self-explaining, these dharmāḥ are not different than their self-explaining, judged as truly real, not delusional. (SA 296, 因緣法)