OP is right -- too confusing.
Screw this whole SI unit thing. BTC is a unit already, and it's widely accepted. This unit changing idea is so obviously pegged to USD value, that it means we'll go from mBTC, onto uBTC, satoshis, etc. etc. Or "bits" -- what the hell is that? Just some made up crap.
BTC is a unit.....
If you screw the metric system have fun without measuring in kilometers, kilograms, centimeters, Celsius, ampere, volts, ohms, watts, joule, newton, pascal, kelvin, gigahertz, terabytes, and what not.
Have fun with your feet, bananas, inches, spider legs and whatever tools you have laying around there caveman.
You're missing the point. Apparently it went way over your head. I have no problem with the metric system.
BTC is already a unit. What legitimate reason is there to peg it to fiat value -- seemingly the only justification for perpetually changing its unit? Every few years, we gonna change the unit? How many different wallet standards will there be, and how many people are going to send irreversible payments in the wrong order of magnitude?
The dollar is perpetually being devalued -- the inverse of BTC. Do we constantly change the dollar's accepted unit, as it loses value? No; it is a standard that people are used to and understand. Same goes for BTC.
A kilogram is a not a different unit from a gram just like a gigabyte is no different from a megabyte,
There's a unit (gram, bytes, meters, whatever) and a prefix to show the correct order of magnitude so you will at most need 2 decimal places (which we are used to) so if you use the metric system, no matter how small or how large, you can always use the same single unit without needing many decimals. For example, need to measure a distance traveled by car? Use the prefix kilo (which means multiply by 1000) on the unit of distance (meters) and you'll measure distance in kilometers so you don't need to add 3 zeroes and the distance traveled is probably less than 1000 kilometers (otherwise you should TECHNICALLY use megameters Altough noone really uses that)
However meters or kilometers would be quite useless if you are measuring your windows in order to place new frames. You'll need more precision so you divide by 1000 to get millimeters. (Or centimeters, but millimeters is usualy prefered in this case)
Is that not exactly what we want? Using one unit (bitcoin) without using more than 2 decimals? Welcome to the metric system.
It's the bitcoin that is the unit, and milli, micro that is the prefix. Need to buy a house or a car? Bitcoin will do. Need to buy a bread? Millibitcoin will do (for now)
Is it the year 2018 and is bitcoin worth a million?
Need to buy a yacht? A couple of bitcoin will do
Need to buy a car? Millibitcoin will be enough
Need to buy a bread? Microbitcoin will be the best choice
Never need units larger than 1000 and never need units smaller than 0.01
Want large numbers? Measure in microbitcoins and enjoy feeling rich by owning over a million micros
Have you ever seen someone say: well I went on vacation to Spain and it was only 20 millimeters travel?
Of course not! We automatically use the prefix that fits the situation. If the prefix makes it so that the number is between 999 and 0.01 than you use the right prefix. Well technically if we want to be strict about it you should always use the unit that is between 999 and 1.00 (called engineering notation) but either way works.
By the nature of having very many decimals and very large as well as very small numbers (up from megabitcoin, which will probably never be used down to almost nanobitcoin which might be used in the future) makes bitcoin absolutely one of the prime examples of why the metric prefixes were invented in the first place.
Let me explain again. The sole purpose of Metric prefixes is to avoid having to use very large or very small numbers, while having only 1 standard unit of measurement. To avoid conflicting and confusing units and unit conversions.
Would you rather have millimeters and centimeters than having inches, yards and miles? Don't let bitcoin fall to the imperial system with all their weird 'bits' or we might as well introduce the banana scale.