That's a good question. I'd personally argue that it's different in that the adblockers are not an inbuilt part of Firefox, they're made by extension developers. This is built right into the browser.
This isn't my wheelhouse so take it with a grain of salt, but an argument against link summarizers that I've heard is that it takes views away from websites that could be generating revenue for themselves. Instead an LLM scraped their content and fed a summary directly to the user.
There are a bunch of flags in about:config you can check as well, if you wanna be extra sure they're turned off. Just search for browser.ml. There are more but this was all I could capture in one screenshot. Bold means I had to change it, which means it was on by default. That said I'm using CachyOS repos, not the direct Arch ones.

Gonna get my news one pixel at a time just like grandpappy did on his 9600 baud.
It's actually incredible for getting real reading done without my ADHD taking over and opening up 30 tabs of "ooh whats this?"
I do, in fact. I get that they are typically open-source, and I also understand how ridiculously difficult it is to create one from scratch. If LibreWolf or whoever want to make privacy focused browsers based on mozilla foundation or google's work then that's fine and I support it, but I'm personally curious if there are any mainstream browsers that don't have any (or minimal) reliance on google and mozilla foundation. Someone pointed me towards an engine in development Servo which looks quite interesting! Hopefully there will be a browser based on it soon.
https://www.spacebar.news/servo-undercover-web-browser-engine/
At the start of the millennium, Internet Explorer used its own Trident engine on Windows and Tasman on Mac, Opera used Presto, some embedded devices used NetFront, Netscape had Gecko, and KDE made KHTML for its Konqueror browser. Those browsers eventually faded away or adopted a competing engine to simplify development. KHTML was the basis for Safari's WebKit, which in turn became Chromium's Blink engine, and Netscape's Gecko engine became the foundation for Firefox. Opera ditched its custom Presto engine in 2013 and switched to Chromium, and Microsoft Edge made the same move in 2020.
This is a danger to the open web in more ways than one. If there is only one functioning implementation of a standard, the implementation becomes the standard. The web becomes to Google what Java is to Oracle. It also means the limitations and security flaws in Chromium affect most other browsers, which became a topic of conversation with Google's recent Manifest V3 transition.
That's still a fork of Firefox, isn't it? I was hoping to find a reasonably modern browser that doesn't rely on gecko or blink. I'd be okay with a WebKit browser but I don't have a Mac.
If anyone has any suggestions for browsers hook me up, I'm running out of browsers with thier own engines to try. I don't see much point in using, say, LibreWolf if the engine is still the same as Firefox (Gecko in this case). Maybe I'll give NetSurf a try and pretend like it's 1996 again.

edit i don't see much point because doing some about:config shenanigans is nearly the same amount of work to me as switching browsers.
Had a co-worker who would eat at their desk so they could use their whole actual lunch break to take a shit lol. The only thing I regularly saw him eat was butter chicken.

Thanks for adding that detail, makes sense. I was thinking the link previews were yeah more like the google results. Hover over and not have to go to the site.