This is probably just coincidence so don't take me too seriously but here's what I've noticed:
The professors of my biology/chem courses: "Hey buddy, don't be afraid to ask questions we've made sure to try and make things easy to understand. Here are some extra resourses for you if you're having trouble. We've structured the marking so that you have lots of opportunities to catch up if you have a bad week etc. Good luck! So proud of you all! 🥰"
The professors of anything to do with math or tech:
"LISTEN HERE YOU LAZY PEICES OF SHIT. IF YOU DON'T ALREADY KNOW EVERYTHING I'M SUPPOSED TO BE TEACHING IN CLASS THEN FUCK YOU. WE HAVE ONE TEST AND IF YOU FAIL THAT THEN YOU'RE FUCKED AND IT'S YOUR FAULT FOR NOT READING THE EXTRA RESOURSES I HID WITHOUT TELLING ANYONE THEY WERE THERE. WHAT? YOU HAVE A QUESTION? THAT'S A YOU PROBLEM, IDIOT! 
"
the Chem instruction at my R1 school was very "fuck you" as well. my advisor recommended everyone to fill out some forms and take in summer session at a local community college the uni has an agreement with for specific courses.
the pattern I noticed was, as others have said here, instructors at research institutions who do not want to be instructors.
it's fucked up because instructor labor brings in a shitload of revenue to the institution, but it's a dead end at big unis because research dollars are so mega. so it's a "burden" of researchers and lecturers/instructors are sidelined/lack institutional power.