For 4 years. Then it halves again. And again. People have this distant figure of "2140" in their head as when the subsidy goes to zero and we can just kick the can down the road and we don't really need to care about fees until then, but in reality most people using bitcoin today are going to live to see the point when the subsidy becomes negligible. It's only going to take 20 years for the block subsidy to fall below 0.1 BTC. Even if we think bitcoin will be $100,000, then you are down to only $10k per block which is around 2-3% of what miners are earning right now per block. And it only goes down from there. Unless you believe bitcoin is going to be worth $10 million or more within in the next 20-30 years, we need a competitive fee market.
I agree with having a competitive fee market, and we should absolutely not allow free lunch but there is of course, several considerations. The fee market right now is largely elastic, users mostly don't care if the fees are high because a good proportion of them can delay their transactions for a later date - at least for the average Joe who are trying to use Bitcoin as a daily functional currency. If Bitcoin were to try to break into the mainstream and be more integrated into our society, I expect more settlements to take place on second layer but there has to be a capacity increase to accommodate for the first layer as well.
With regards to block size, if we were to increase the block size, say 2-3 times, I would think that there would be times where transactions paying 1 sat/vbyte can be confirmed, and there would be times where it would require substantially more. The fluctuation in fees and the vast increase in the number of transactions can potentially offset the security concerns that may exist.
If we were to keep the fee market overly competitive, ie. $20 for a single transaction, it can dissuade people from using Bitcoin as a currency when there are multiple other payment methods as well.