I can't speak for the Bronco, but I have been driving a Jeep most of my adult life without lockers in Michigan. I also never had any problems playing in the snow. Coming from an AWD to a part-time 4WD, you would just have to remember to turn it on.
With that said, if you ever plan on getting bigger tires or anything, you really would want the 4.27 diff ratio that comes with the rear lockers, over the 3.73. Otherwise, you would have to pay to increase the diff ratio, which will cost you more than the $795 for the factory upgrade, and that would not have the quality you would get from a factory differential... Plus you would have a locker!
Would you need it? No. Should you get it? I would recommend to anyone to get it if they ever plan to do any upgrades to the vehicle, just for the diff ratio alone! Having the rear locker would be a pleasant bonus.
On order: 2022 Non-Squatch, 2.7L, Badlands, Lux package, 4-door, MIC top, tow package