I teach. I can say that I have never had direct pressure to pass students or raise grades, but there are two issues that I run into related to grades.

First is the ever-growing methods of academic dishonesty. I do not have enough hours in my life to create and design new homework that prevents cheating. It's possible for some assignments, but not all. I don't give up on cheating detection, but this leaves tests and participation (be it simply turning in work or in-person) as the primary grade-changing events for many students.

Second is the issue of student "litigation". It is not unusual to find a student that will fight to get their 4.0 by attrition, and that requires very good record keeping on the professor's part, taking away from time for other tasks.

My situation is at an extension of a very large university. We focus on teaching and student connection, not research. I know that these experiences change drastically when professors have graders and a research program taking their time away from teaching duties.