If you drive a car, it makes little difference what brand it is: all cars are driven in essentially the same way. The same applies to computers. If you have a Windows PC, the user interfaces won’t be affected by your computer hardware. This is definitely not the case for industrial robots.
The way you program an industrial robot strongly depends on the robot brand. You might think that a robot program looks like C++ or Visual Basic. The truth is that some robots are still programmed in assembler-like languages.