People like David Pearce certainly would be tempted to do just that.
Well, of course you can modify someone else's terminal goals, if you have a fine grasp of neuroanatomy, or a baseball bat, or whatever. But you don't introspect, discover your own true terminal goals, and decide that you want them to be something else. The reason you wanted them to be something else would be your true terminal goal.
trying to earn a university diploma
Earning a university diploma is a well-understood process; the environment's constraints and available actions are more formally documented even than for self-driving cars.
Even tackling well-understood problems like buying low and selling high, we still have poorly-understood, unfriendly behavior--and that's doing something humans understand perfectly, but think about slower than the robots. In problem domains where we're not even equipped to second-guess the robots because they're thinking deeper as well as faster, we'll have no chance to correct such problems.
...you don't introspect, discover your own true terminal goals, and decide that you want them to be something else. The reason you wanted them to be something else would be your true terminal goal.
Sure. But I am not sure if it still makes sense to talk about "terminal goals" at that level. For natural intelligences they are probably spread over more than a single brain and part of the larger environment.
Whether an AI would interpret "make humans happy" as "tile the universe with smiley faces" is up to how it decides what to...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.