We're not sure most legislators want to do anything to paintball guns at all - it just happens that the way the bill is written, paintball guns are getting lumped in with replica airsoft guns.
But, the current bill would absolutely ban many paintball guns. Yes, if your gun is entirely brightly colors that would be OK, but I personally can not think of a single paintball gun in existence right now that would be legal under the new bill.
Plus, most guns need an air tank to work. How many bright pink air tanks have you seen? Does an air tank count as part of the gun that must be brightly colored? The law doesn't say - and it's not something you really want to find out about in court.