Allowing arbitrary code execution by default cannot be safe.
90% of what JavaScript is used for is totally unnecessary and only makes sense in an ad-based web.
Windows Phone 7 was a brilliant example of this. It was one last attempt by a large player to unite social media sites and messengers into one UI and interaction framework, and it was the most fluid, beautiful and pleasant OS I've used. Now that kind of interoperability would be borderline illegal. When you strip control away from devs about how their data is rendered, the results are generally more beautiful, not less.
I'm guessing that interaction reminders are those modals that appear when you go to close the tab, or prompt you to subscribe when scrolling down further. I would classify both as totally unnecessary and making the experience worse for users. They also do not require arbitrary code execution.
Cookie popups are a result of the ad-centered, panopticon-enabling web.
I know what I'm describing is far and above nojs. What I'm trying to get at is the motivation for disabling js, and what the web would look that if that principle were followed to it's logical conclusion.
Beyond the privacy/security benefits of not running arbitrary code in your browser, the web is a lot faster without JavaScript involved.
My approach is to use the NoScript extension and only allowlist the minimum to get web apps to run. Most news sites work fine (i.e. are readable) without JS, so often I just see faster page load times and decreased data transfer. Even fewer ads and decreased tracking are great too, but secondary benefits.
I don't think my browsing habits are different since adopting this approach. I use NoScript to cut the junk and improve the experience.
All of them work perfectly fine without JS! And only Stackoverflow (Markdown Preview) has a reason to use it at all.
Unfortunately the web is in a state that's worse than just javascript... it's regressed into only supporting certain browsers cough chrome cough. Just one example (i've got more personally) from recently: you can't book flights in air india's website with firefox, but it works in chrome.
I'm using Qubes OS, which allows to run many sandboxed Firefox instances, with colorful window frames. I run JavaScript without a fear, since each Firefox runs in its own VM, with no data in it.