I'm not really sure I get the point. Simply opening a browser means you're allowing the browser developer to run code on your computer, and you're giving them permission to do so by downloading, installing and using their software.
- The browser's source code is available so I can see what it does.
- The browser is distributed by Debian who also distribute most other software I use so there is 1 organization to trust instead of 1000.
- The browser is not downloaded and executed and upgraded automatically, so it's possible for me to know what code runs and doesn't run on my computer.
- There are multiple browsers I can choose from. I can't choose which javascript to use when I visit a website.
- I can modify the browser if I want it to work differently (which I have actually done). It's harder to modify the javascirpt on a website because it's updated every time and very tied to the rest of the site and is often unreadable.
- Modifications can be distributed, so if I make a better version, other people can use it and forget about the original version if it was bad.
This is not about me. It doesn't matter what most people feel or what they want to do. It's the situation where people are expected to run often invisible code written by untrustable people that is wrong. People should have the right to know and control what their computer is doing, even if they don't want to use that right. The current situation doesn't allow them to have that right.
> I think most people expect that they're getting some service (like a browser) by allowing developers to execute arbitrary code
The problem is that it's too easy for developers to use other peoples' computers for their own benefit when the current situation of the web is that people automatically let random people on the internet run code on their computers. It happens all the time. That's why they should not have this freedom.
I don't know what you mean that people like exactly but it's definitely possible to let people use software in fair ways so they don't have to give up anything. A lot of times the use of javascript is unnecessary so removing it doesn't make any difference for the user.
> the exchange (you run arbitrary code on my device, I get software I want to use) is helpful to most people, not harmful
It doesn't matter that the exchange is helpful if it happens in an unfair way. Compare this to prostitution. It's illegal (at least the other side of it) in many countries. But everyone involved gets what they want or need and the exchange is helpful to everyone, so why is it illegal? I guess it's because some people just think it's wrong and that it's an exchange that can't happen in a fair way even if everyone involved is happy with it.