Different oems started switching refrigerants at different times. Some waited a long time and hoped someone would come up with a better replacement seeing as 1234 is expensive and flammable, others switched earlier. For example FIAT based Chrysler’s (Cherokee renegade Pacifica 200 dart etc) went to 1234 as early as the 2015 model year, but they left RAMs with 134 until the 2019 redesign. I seen to recall charger challenger 300 not getting 1234 until 2015 or maybe later but I could be mistaken. It’s not as bad now but in the beginning it was horrible, we’re one of the only shops in the area with the right equipment so we did a lot of body shop ac charges, these shops would quite evac/recharge as if it were 134, then lose their butt when they got the bill. It’s also a painstakingly long and annoying process to charge with 1234, a lot of hoops to jump through including doing your regular vacuum and leak test, then to charge it does another 5 minutes vacuum, 5 minutes leak test, partial charge, prompts you to check for leaks with a sniffer, recovers the partial charge and weighs to verify no leak, another vacuum, then it will do a charge, not nearly as quick and simple as a 134 charge