it is a lot more about politics than I had originally imagined.

That's not webdev, that's life in a nutshell. Most people don't understand how many interactions, ranging from mundane greetings to promotions and partnerships, are based on politics. We are, fundamentally, emotional creatures. Even what we believe to be entirely logical is often rooted in emotional drive.

Your coworkers do not really care about you all that much

They care about themselves. If you want people to like you, elevate them.

People will belittle you if given the chance.

Most people are trying to establish themselves in the social hierarchy. If they can establish you as "below" them, then their rank inherently increases. You have probably engaged in such a behavior without consciously realizing it.

There's an art form here. Being humble is a necessity, but being incessantly apologetic will get you thrown under the bus. People will use you as a scapegoat to save themselves if they think you're likely to absorb the blame. On the other end, playing alpha dog all the time is putting your insecurity on display and will alienate everyone around you. Learning to identify when people are acting to protect their ego vs being vindictive is important.

This job really isn’t that good for introverts.

This industry has more introverts than most every other industry I've seen. The level of collaboration is largely going to depend on the size of the company. At the extremes, in an "enterprise," your work is not yours, and you'll spend more time talking, writing planning, testing and reviewing your work than you will building things. In a mom and pop shop, you can create an unholy spaghetti disaster and have perfectly happy employers who think you're a rock start.

You really don’t want to ask questions.

There's a balance here too. Juniors are typically afraid to ask questions, because the nature of their questions expose their gaps in knowledge. To that end, perhaps ironically, mid to senior devs are much more liberal with their questions, because they're comfortable with how much they know.

But they're the best way to learn. As a general rule, don't ask questions you could probably google. Do ask questions which aim to flesh out plans, and the line of thought someone presents.

You’ll leave the conversation more confused then when you began

If you're overwhelmed by the volume of new concepts introduced by a question, take notes and study. Learn to identify "rabbit holes" in answers. It's true that if you turn an explanation into a course on a topic, you'll get resentment. No one wants to be impromptu professor for complicated topics.

That said, you should get used to this on some level. If you aim to excel, you'll be cramming your head full of new information daily for the rest of your career, but the feeling of being disoriented will begin to subside.

This is a very dude-bro culture

This varies, a lot. I've encountered entire web shops run entirely by women. Some cultures are essentially frat parties. Some are mechanical and joyless. Some are a little too laid back for their own good. Cultures across companies are as varied as people themselves.