There would be no point. Focus on users, not miners, for a monent. The have a choice:
Option 1. Hard forked chain that that pays more to miners
Option 2. Hard forked chain that does not pay more to miners
Users would choose #2. Miners would choose #1
Miners are by definition sellers of bitcoin, users are both buyers and sellers. Chain two would have both sellers and buyers. Chain 1 would have sellers but no buyers, and would therefore have no value. ASIC miners would face the choice to waste electricity mining a worthless coin or shut down.
Options 1 and 2 are different coins, that will have different market prices and different expectations of survival.
Already explained that users and only users can give market value. Miners can only hold or sell, but they have no reason to buy. If you don't attract (non-mining) users, you're dead.
Coin 1 is just the same old bitcoin
It's not. It changed. With a bit of forward looking, one can easily see that it would be changed again.
After all,
repeat your plan, exactly as you have stated it:
If miners can fork the protocol to double their rewards once, why can't they do it again? If they can, users will recognize that, and avoid such a coin like the plague, as it is sure to be diluted to nothing.
Your plan, by its own mechanism with no assumptions about alternative mining, fails, because it only succeeds if you stop the game after one iteration, yet the game itself contains no mechanism to prevent such repetition. QED