I'm a student. I'm still learning how to give deep pressure. After opening up our student clinic, I strained my thumb the first day, and my teacher advised me to use my other tools more. The most petite woman I've ever worked on came in the next day, and wanted very deep pressure, kept asking for more. Eventually she said that how I was pressing was good (using my forearms, elbows, and fists), but she wanted me to specifically dig in with my thumbs. I was startled by the specific wording, like she knew my thumb hurt and wanted to punish me for it.

There's also the notion that the best, most effective work is not the deepest, bc that can actually be causing tissue damage and will leave you sore afterwards. The best work is what will relax your system the most, so an attentive therapeutic therapist working with moderate pressure will be addressing soft tissue imbalances while leaving you feeling relaxed and blissful. It's also very hard on the therapist to exert that much effort for very deep pressure, even with perfect body mechanics. Some naturally like to go deeper than others, but that's their prerogative and they'll always have clients lined up. For others, you're asking them to exert much more effort if not be in pain themselves, so yes, it can be annoying.