We are talking about future proofing so let's make 1 BTC = $100,000 for easy math.

Suppose Joe blow wants to order a $5 cheeseburger in BTC. Here's a few different scenarios:

A. "That'll be 0.00005 BTC please."
B. "That'll be 0.05 mBTC please."
C. "That'll be 50 uBTC please."
D. "That'll be 50 bits please."

A and B are eliminated right off the bat because nobody wants to recall how many zeroes they've put after the decimal.

This leaves us with reasonable C and D, but the word "bit" is far more marketable than "micro-BTC". Micro-BTC just doesn't roll off the tongue like bits does.

For those who say we have MicroBitcoin already, it's not about us... we get it, we're fine. We're already invested into BTC. Get over yourself. It's about widespread adoption transcending mathematical literacy, and "bit" is the ideal solution concerning avoiding decimals as well as ownership psychology.