My family's wealth has come from animation, I know animators, and I was going into animation before I decided to become a software engineer, so maybe my opinions on this mean something.

What distinguishes animation and most other industries from software is individual leverage. A fed up software engineer has a fairly decent shot at either working freelance or starting their own operation. This is possible for animation, but there's way more of a hurdle in competing in the market with an independent company unless you have prestige or lots of money. It's really not easy to make substantial profit with a shitty animated film(unless you can afford exceptional marketing, and even then...), and it can take years of making no money to produce one. Contrast this with software, which has a possibility of being profitable in the first month, and can be improved over time, whereas with films and shows you pretty much have a few shots or just a single shot at doing it right. In other words, most animators know they can't just strike it out on their own if the going gets tough, which is one reason why unionization is more common in animation. You'd better be insanely talented if you think you're going to make a living as an independent animator, and most animators aren't excellent at all aspects of animation. There aren't many "full stack" animators. Believe me, I tried to be one. There's very disparate skills that go into making something that's production quality.

There's also a general cultural difference between animators and software engineers. I'm painting with a broad brush here but, in my experience, animators tend to place more value on prestige and there's way more workplace politics at animation studios than I've ever witnessed on any software team I've joined. There's a prestige factor with software, too, but I don't think we make as much of a value judgment between someone who's a Googler and someone who's a freelancer. Again, just my opinion. Since animation is a part of the entertainment industry, it inherits the good and the bad of entertainment in general, which includes not highly valuing anyone except directors and producers. Most everyone else, besides big name actors, are expected to be treated like trash and disposed of when they aren't immediately needed anymore. One reason I ditched animation, besides my lack of talent, was that it can be very challenging to stay working at one studio for a long period of time. People do it, but they're the ones that seem to work a lot of extra hours(for no pay) and have a handful of useful talents that make them worth having around between projects. Basically, animators are used to being treated like crap and have a different sort of work ethic around it.

Entertainment also attracts a different type of person. Again, another generalization, but there are way more neurotic and crazy people in entertainment, animation included, than in other fields. I think that's because it attracts both visually creative people and those who are bent out of shape easily if they aren't the ones winning, since the field can be so incredibly competitive. This leads to a dichotomy of needy animators who are always doing anything they can to "get their foot in the door" and tyrannical leads and directors who don't value their subordinates because they see themselves as Hollywood moguls. Of course this isn't true across the board, but my family members and friends in the field all have multiple stories of leadership treating people like garbage and getting away with insane things that you think would have been rooted out in the #MeToo era. In the end, it's all seen as a necessary evil on the journey to the glory of producing successful art. I don't think this is nearly as common with software(and many other things) because the average person doesn't give a flying F about software, so the drive to achieve prestige is very limited.

So to summarize, for various reasons, there's far more ego involved in animation, which leads to people with power treating everyone like crap.

Oh, before I conclude, we can't forget how much it costs to produce an animated film or TV show that meets the current expectations of the industry. Even though I think a wall is being hit in terms of just how much visual spectacle they can produce, the precedent to pay animators poorly has been set long ago when new studios were popping up and desperate to make something. Other industries, such as software, never went through the same cost hurdles during infancy; even back in 1996 you could start a software company easily with just one guy behind a single workstation and maybe a server rack.