It's about scope. The "ideal" design one pattern is supposed to be separation of concerns - the devolution of performance and responsibility into units that can be built and tested independently.

This is fine when that design pattern fits the domain. But some domains require global context, and it isn't useful or possible to strictly enforce separation - because you end up passing parameter bundles around and managing all those local scopes introduces more bugs than implementing a global context.

Multithreading is a different issue, and is a different kind of domain requirement. If you need multithreading and have a global context, you have a very interesting problem to solve.