Earlier quoted context omitted.
Android: firefox for android, or the plethora of adblock browsers out there iOS: adblockers are natively supported through "content blockers", plus there's a plethora of adblock browsers
But not possible in native apps which have largely supplanted the use of web pages.
That said, because ads are inserted by third parties, you can often block ads with DNS and/or VPN. It’s a shame that iOS has never allowed changing the DNS while on mobile networks, though.
Really though, I miss when we were building open standards for content though, like RSS and podcasts.
Feels like a different era of the Internet, as we never saw an open standard take off for ChromeCast/AirPlay2 or the mentioned-on-stage open standards for FaceTime. Even the RIAA is trying to lock down music again by promoting MQA (Tidal) over FLAC (HDtracks, Amazon).
Closest thing to “open” that I can think of recently for content would be HLS streaming, which optionally supports encryption, but is otherwise open to use or implement.
Given recent history, I think it could go either way, but I doubt users will ever fully accept a closed web, so as long as the web provides open alternatives on every platform, we’ll still be in the clear... for now. :)