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! 
"
Our university's researchers had some teaching requirements. You could easily tell which people resented it.
It's an awful idea. Teaching is a whole ass skill that needs to be trained and developed, and these just throw lab nerds in to a classroom and expect them to be good at it. The best professor I ever had was a guy who started out teaching grade school, taught middle school, taught high school, and eventually ended up teaching at uni. Didn't have a PhD, knew everything about his subject backwards and forwards, and was genuinely good at conveying it to the class in ways we understood. It made an enormous difference compared to professors who resented being there, or who were trying but didn't have the necessary experience and technqiue.
I wonder if it would be more productive to pair the non-teacher researchers with someone who does have a teaching background for these sorts of cases.
I feel like there might be some value in having your professors actually have to do some teaching/work with the students, can't just be isolated away in a lab 24/7, but you definitely can't expect people who are primarily researchers to all suddenly be great teachers as well, so for the students sake they should have some help.
Additionally, the knowledge to teach a lot of this stuff is only known by research profs, so working with someone to do the teaching part would be quite good.
This is true, I had a lot of professional former chemists as professors and like half of them didn’t really get the teaching part haha.
I believe this applies to most universities, at least for professors.