It seems that the additional steps required ... to undo the wire nuts, salvage the pigtailed connector half ... and reconnect are an unnecessary complication. Heck, if I'm going to play with the wire nuts, I might as well continue to do it the 'old fashioned' way.
Indeed, I expect that the first thing to happen will be for these connectors to be cut off and discarded. Take the wire nuts out of the equation, and at least you have 'convenience' as a selling point.
Put half the connector on the ballast .... I don't see ANY change at the fixture factory. The only obstacle is the lack of interchangeable plug patterns.
If the connector makers aren't willing to work together, the ballast makers will make the decision for them. That market is so lopsided that Advance, acting alone, will decide the issue all by itself.
Which, of course, brings up distribution conflicts. If the WAGO pattern is chosen, places that carry Ideal, T&B, or who knows what brand will be at a disadvantage. This is exactly the situation NEMA standards exist to prevent.
You might as well have every receptacle maker use a different pattern ... and have the customer fit the plugs to their appliances.
