If there is no farming incentive for providing liquidity then everyone providing liquidity will automatically lose money from "impermanent loss" every time prices move. There would be nothing to gain from providing liquidity, so no one would do it.
AMM is superior to order books because the farming mechanic incentivizes everyone to all throw their liquidity into the same pool, increasing liquidity exponentially compared to an order book and greatly reducing slippage in both directions.
Without yield farming, AMM is pointless.
But at the same time trading fees are part of the yield.
So you could jack up trading fees to like 1%-2% and pay the LPs with that.
You can't just reject reality.
2 + 2 = 4
It's already happening.
It's already happened.
AMM mathematically provides more liquidity to the market on a dollar for dollar ratio.
People are using them.
These are facts.
Literally no one is saying otherwise.
Risk: meet reward.
Providing liquidity is far less risky than trading.