I'm not concerned with active or inactive coins, only how many coins have been generated.
It has no sense. Inactive and dead coins simply doesn't exist for market. You can't predict destruction or inactivation rate in the future, so you can't use fixed emission rate to keep constant coins value. It's something like the nuclear reactor control by using a sledge hammer. One small mistake and... BAAM 
You need adaptive algorithm, which will be based on active coins volume.
It also creates a problem because an rogue agents can buy coins and destroyed them, lowering the inflation rate and making the crypto that is designed for inflation, actually deflationary. Thus, destroying the whole purpose of your inflationary coin.
I do not want to judge between active and inactive coins. It is a benefit of the protocol that the inflationary rate should be based on all coins mined rather than coins in circulation, active or inactive.