BLUETOOTH NOTIFICATIONS RESOLVED!!
I won’t venture to guess why but apparently Siri must be allowed to announce notifications to be alerted while using Bluetooth. Go to settings, then to Siri search, then to announce calls, choose whether you want to use headphones or headphones and car, then go to announce notifications, and do the same. Now both calls and notifications will alert through the Bluetooth speaker.
iPhone 14 Pro, iOS 17