What weighs us down?
I think I have been very lucky in many regards and I guess I am also by nature a rather happy camper. But of course I see people struggling with all kinds of things, including toxic environments. As a professor one can often help quite a lot even with relatively little effort. There is listening, there is giving advice, there is having a word with troublesome people and so on.
In my experience, toxic environments don't tend to originate from an institutional structure per se, though that structure may of course foster or ameliorate toxic environments. In my experience, toxic environments tend to originate in specific people's behavior, which is often caused by a lack of empathy.
Personally, I think that empathy, i.e., the ability to see things from the perspective of another person both intellectually and emotionally, including the skill to see oneself from the perspective of others, is a key new skill to acquire for the future. Being able to empathize well is clearly very valuable for the purposes of leadership, supervision and teaching, for giving presentations and for writing papers, for general communication skills and, arguably, for a rich and satisfying life in general. If there was an empathy training course, I'd take it!