I was reading an [article](https://www.indiatoday.in/technology/features/story/do-airtel-jio-act-spy-on-fiber-internet-users-isp-supplied-routers-raise-privacy-digital-rights-concerns-1844534-2021-08-24) discussing the deleterious effects of ISPs locking down customers with mandatory antiquated routers supplied by the very same ISP while providing *fiber-net* connections. One point in this article that I didn't quite understand is when one of the advocates against this issue mentioned that the ISP could possibly snoop on the user's browsing behavior (emphasis mine).

> 
> From a privacy perspective, **Airtel[\*] should not have access to what I am
> accessing on the internet**.
> 
> 
> 

\*Airtel is the ISP

Doesn't the ISP(Airtel in this case) anyway know the domain which I'm browsing because, well, it's my ***ISP***? This [DuckDuckGo](https://spreadprivacy.com/protection-from-isp-spying/#:%7E:text=ISPs%20can%20still%20see%20the%20domain%20of%20the%20website%20you%20are%20visiting%20(everything%20up%20to%20the%20%27/%27).) article appears to indicate that the domain name of the site is anyway visible to the ISP, even in case of HTTPS sites. What additional information can the ISP glean from the router that isn't already available with it?