The EU’s planned KIDS Act is causing unrest in the Fediverse, the network of independent servers around Mastodon. Critics warn of age verification on every single server and foresee the end of decentralized social networks.

My home instance is outside EU jurisdiction.

It may be very damaging for the Fediverse, but even if the EU outright banned all ActivityPub servers, that wouldn't force an end to the Fediverse.

And the rest of the world?

The Fediverse does not end at the external borders of the EU. The draft applies to providers regardless of their location as soon as they offer their service to users in the EU (Article 2) and requires them to have a legal representative in a member state (Article 24).

You have to meet the US definition of doing business in the EU for the US legal system to enforce any EU rulings against US-based instance operators, and simply having a service accessible to EU users is not alone sufficient to meet that bar. My guess, though I'm not familiar with other legal systems, is that they likely have a similar bar. The EU itself probably uses a similar jurisdictional bar, which is why, for example, EU-based server operators are not subject to Iran's death penalty over blasphemy just because an EU server might be accessible to an Iranian user.

The EU might seek to compel EU-based ISPs to block EU users from having access to US-based instances, prosecute EU-based instance operators that federate with US-based instance operators, partition the network, and that might be adequate to cut off EU-based users from US-based instances, but it won't be a worldwide ban via a legal route.