Not that it typically matters in a practical sense* (Unless you're writing to a register for a device)...

However I've always viewed Little Endian as 'bit 0' being on the left most / lowest part of the string of bits, but Big Endian 'bit 0' is all the way to the right / highest address of bits (but smallest order of power).

If encoding or decoding an analog value it makes sense to begin with the biggest bit first - but that mostly matters in a serial / output sense, not for machine word transfers which are (at least in that era were) parallel (today, of course, we have multiple high speed serial links between most chips, sometimes in parallel for wide paths).

Aside from the reduced complexity of aligned only access, forcing the bus to a machine word naturally also aligns / packs fractions of that word on RISC systems, which tended to be the big endian systems.

From that logical perspective it might even make sense to think of the RAM not in units of bytes but rather in units of whole machine words, which might be partly accessed by a fractional value.