It's all about relativity.

If you make $1 million a year, then you can afford to buy full fare whenever you want to fly J class. Then what's $600 increase per year per ticket to you? Those that buys full fare on a consistent basis are likely those that does not have to pay from their own pockets or are wealthy enough to do so.

If you make $100K a year and want to fly J class, then you definitely will buy the lowest upgradeable fare instead of a full fare J. In this case, $200 increase a year PER TICKET is not insignificant.

I maintain my stance that people will notice the new upgrade policy.