To be fair, 60Hz to 75Hz is barely noticeable even by those who are used to notice these things. If you can't tell the difference, it's understandable.

Then, the bigger the screen, the more noticeable high refresh rate is, because it covers more of your field of vision. So in a small iPhone screen it's not easy for everyone to notice (and then there is the fact that iPhones rarely go to 120Hz anyway which is an absolute mess by itself but that's another topic, so your 15 Pro probably rarely goes above a noticeable Hz change anyway).

However, if you get a 144Hz or above, 24" and above monitor, you will IMMEDIATELY see the difference against your 60Hz monitor. Even moving the mouse feels more responsive and accurate. Makes targeting stuff with your mouse easier. Reading text while scrolling is possible also. It unlocks a new world, it's not only for gaming. Casual and work use also benefit a lot from high refresh rates.

When it comes to my phone, I can tell the difference between 90 and 60 Hz. I prefer 90 Hz but I would be okay with 60. Ideally I'd like the highest refresh rate I can get inside my budget when I have to buy a new device with a screen. One annoying limitation is that all the video is played in 24-60 Hz. I notice it when things move with any kind of speed or when I'm looking at background object and the camera moves.

All things considered, it's a minor annoyance. My quality of life wouldn't change if I were limited to 30 Hz.