Calling it now: they will reverse this decision by December after they realize how many gmail customers they are losing.

Unless you have insider knowledge, this seems incredibly unlikely. Do you really think most GMail users even understand what this functionality is, much less use it? Google is many things, but they're not suicidal. I'm sure they did the math of the ongoing cost of supporting this functionality, versus whatever revenue people who care about it (and are still paying nothing) might bring in and realized its a cost savings for them. Losing 0.3% of all users is likely in their interests.