Puranas generally have Panini's grammar, i.e., not Vedic Sanskrit. Panini is supposed to have lived around 400 BC.
Sanskrit grammer vs Panini's grammar.
Is that something akin to spanish vs Italian grammer?
IMO, not likely since both these are latin based. Too close already in word roots etc. But the grammer difference would differ in what way Formatting to plantain leafs' parameters?
There are many different Personalities ---devas, Maharajas, Santas, yogis, warriors, etal from distant parts . . . on the universe ... spanning eons ---that fill the millons of verses in the Vedic Literatures. These different Personalities are QUOTED VERBATEM.
Capturing a persons voice and inflection and other subtile nuances are part and parcel of great literature. That is the source of the different Meters of the spoken word, as is recorded as the "Histories" aka "Puranas".
All readers of unabridged editions of any Purana will easily notice the plethora of personae dramtica entering and exitting ---like a vast Soap Opera of Characters ---these Characters of the "History(s)" are known as devas, Maharajas, Santas, yogis, warriors, etal from pre-Western History.
That is WHY INDIA IS SO WONDEROUS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Because of its provanance.
Hindu provanance is the Next Frontiere