There is still debate as to which will win out (https://www.nytimes.com/2018/09/20/business/vehicle-communic...), but GM, Toyota, and Volkswagen seem committed to DSRC. As they are the biggies, my bet is within 5 years most new cars, some new pickup trucks, and some new delivery/heavy trucks will be using DSRC.
How useful will that be?
DSRC transmits a "Basic Safety Message" 10 times per second (range 1000 meters), containing velocity vector, pitch/roll/yaw vector, vehicle weight, status ("braking", "skidding", etc) and, critically, position. Current GPS (particularly in urban canyons) may only give 10m accuracy, or worse.
But if we could get 10cm accuracy (maybe with some kind of publicly deployed differential gps?), then a whole set of advantages become apparent.
1) Your Heads-Up-Display could warn of a (DSRC-equipped) vehicle that's about to blow through an approaching stop sign and will collide with your projected position. And your auto-braking could be activated.
2) You could be warned on the freeway of a vehicle 5 cars ahead of you that has just slammed on the brakes (because that vehicle just transmitted that info).
3) Special lanes could be reserved for platooning, with cars separated by only a meter or two (0.1-0.3s) rather than 2s. Voila -- much greater lane capacity.
4) If DSRC were cheap enough ($100-200), bicyclists and motorcyclists could buy one, and make themselves much more visible to every DSRC-equipped cager.
5) And if really cheap, many pedestrians might carry them, safe in the knowledge that if they step out into the street, the auto-braking cars will pro-actively avoid them.
And _none_ of these features require any type of cameras, lidar, or other (arguably problematic) self-driving technology. Heck, they don't even require a map.
A final point about privacy -- DSRC was designed so the vehicle identifier isn't anything traceable like VIN or license. Instead, the id is randomized every few mintues (or at least according to https://pdfs.semanticscholar.org/fd03/f4c5f3128db5c08e5e92f2... -- I don't know how GM/Toyoto/VW have implemented it).