I sort of see what you are getting at but I am still a bit confused:

If I have a program that based on the input given to it runs some number of recursions of a function and two compilers of the language, can I compile the program using both of them if compiler A has PTC and compiler B does not no matter what the actual program is? As in, is the only difference that you won’t get a runtime error if you exceed the max stack size?

I think features of the language can make it much easier (read: possible) for the compiler to recognize when a function is tail call optimizable. Not every recursion will be, so it matters greatly what the actual program is.