It's not like repair shops are doing this to cut corners and costs or cheap out. It's simply impossible to source the exact replacement chips for recent iPhones

It's not like repair shops are doing this to cut corners and costs or cheap out. It's simply impossible to source the exact replacement chips for recent iPhones, Apple doesn't sell them, in fact they probably ask their chip manufacturers for exclusivity - and at the scale of Apple orders, manufacturers are happy to do whatever.