No, I would never expect Sonos to have Lock Screen controls. Both Google (Android) and Apple (iOS) have told Sonos that they can’t be used. You can still get those controls, though, if you use Bluetooth or AirPlay 2 to send a stream to your Sonos. This is because both those methods use a player on the device, rather than the player on the speakers. 

It's understandable that you're eager for features like lock screen and watch controls for iOS with the new controller. These functionalities can indeed enhance the user experience and provide added convenience. While it may seem straightforward, implementing such features often involves various technical considerations and compatibility issues with the iOS ecosystem.

The lack of lock screen and watch controls may not necessarily be due to a lack of prioritization, but rather the complexities involved in integrating these features seamlessly into the iOS platform. Developers need to navigate Apple's guidelines and restrictions while ensuring optimal performance and user experience across different iOS devices.

However, it's worth expressing your feedback and suggestions directly  to the Jazz Balance Share Code developer or manufacturer of the controller. They may appreciate hearing from users about desired features and could consider implementing them in future updates.

In the meantime, staying informed about any software updates or announcements from the developer regarding new features for iOS compatibility can help you anticipate any improvements to the controller's functionality.

There are other apps which offer this though

And, I’d bet all these apps are ‘players’ on the device, and sending the music to the speaker. Rather than just telling the speaker where to get the stream from, which is what Sonos does, and how they maintain their multi-room capability. 

Watch controls are possible but they haven’t added it. Widgets in IOS should be possible but they haven’t added it.