Well, they're only doing what they announced already like 1-2 years ago. So we knew it was coming. This is also accompanied by Google making YouTube more restrictive when viewed with adblockers. Google is (somewhat late, to be honest) showing its teeth against users who block ads. I always expected it to happen but it took them quite some time. Probably they wanted to play the good guys for long enough until most users are dependent on their services, and now their proprietary trap is very effective.

On the desktop, you should switch to a good Firefox fork right now. Firefox can also be used but needs configuring before it's good. The forks LibreWolf or Mullvad Browser are already very good out of the box. There's the potential issue of the forks not being updated fast enough, but so far these two have been fast. Mullvad shares a lot of configuration with the Tor Browser, so using it may break some sites. LibreWolf might be "better" for the average user because of that, but otherwise I think Mullvad is the best Firefox fork overall.

On mobile, Firefox-based browsers aren't recommended, because on Android, the sandboxing mechanism of Firefox is inferior to that of the Chromium-based browsers. And on iOS, all browsers (have to) run on Apple's proprietary Webkit engine anyway, but well this is Apple we're talking about so of course it's all locked-down and restricted. It's one of the reasons I don't even like talking about Apple that much, just be aware that as an iOS user, your choice doesn't mean as much when it comes to browsers, and your browser might not behave like you think it does on other platforms.

So on mobile, I'd suggest things like Brave, Cromite or Mull. Or Vanadium (GrapheneOS). If the browser doesn't have built-in adblocking capability which sidesteps the MV3 restrictions, make sure to use an ad-blocking DNS server, so your browser doesn't have to do it. But you still need it. Adblocking not only helps you retain your sanity when browsing the web in 2024, but it also proactively secures you against known and unknown security threats coming from ads. So adblocking is a security plus, a privacy plus, and a sanity plus. It's absolutely mandatory. As long as the ad industry is as terrible as it is, you should continue using adblocks. All the time. On every device and on every browser.

The ad industry is itself to blame for this. There could in theory be such a thing like acceptable ads, but that would require ads to be static images/text, not fed by personal data, and not dynamically generated by random scripts which could compromise your security, and not overly annoying. Since that is probably never going to happen, you should never give up using adblockers. Since they basically fight you by reducing your security and privacy, you have a right to defend yourself via technical means.