well this would be a good idea in a way.
Imagine if a alt-currency only worked upon CPU,
then everyone in the world with computers can jump at it
and earn a piece of the decentralized currency.
With bitcoin, you have to have a ASIC miner,
or a special device to have a share of it,
anything else will be too small to be even worth it.
Billions of people have computers, to have a widespread decentralized
global currency, we would need something that is easily accessible
and mine-able by anyone, within reason.
With bitcoin if you use CPU, you get like 50,000 times slower then a ASIC miner.
And I doubt billions of people or general population will get into bitcoins.
Only nerds and computer tech guys that have their hobbies in computers,
will most likely get into bitcoins.