If the update is urgent, you can try disabling bitcode. I did this and processing finished within minutes... the previous bitcode build is still stuck processing.

Same thing happened with my project. I believe that this is an intentional change by Apple to force developers to start distributing xcframeworks with support for arm64 simulators (M1 Macs). Fat binary frameworks don't work anymore because simulators and actual devices can have the same architecture. The proper solution is to repack the GoogleCast framework into xcframework. You can do this by splitting the fat binary into two using lipo (one for simulator and one for real devices). If you don't want to do this, you can enable "Validate workspace" in build settings. This will enable you to build your project and only output a warning.

I have the same issue... in the developer portal it says "CarPlay Audio (CarPlay framework)"... but inside the provisioning profile there is still the old entitlement "com.apple.developer.playable-content". I contacted Apple a few weeks ago asking for access to the new "com.apple.developer.carplay-audio" entitlement. But no reply from them yet. This long wait time is ridiculous for something that shouldn't take more than a minute for the one responsible. All I'm asking is be able to migrate my app from the deprecated playable content API to the new carplay framework... this shouldn't take weeks or months for them to reply.