Hello, tiffanyd1
Welcome to Microsoft community.
Whether Read Aloud is working properly has nothing to do with account syncing, and this feature does not require logging into your Microsoft account. Network stability plays a pivotal role, with connectivity issues potentially causing the feature to stall or fail to load. Have you experimented with connecting to an alternative network? Furthermore, could any recently installed programs be affecting your internet connection? Or have you been running a lot of programs that require an internet connection at the same time?
Moreover, it appears that your MacOS is outdated. Have you considered updating both your MacOS and Edge? The version of MacOS you use can substantially impact program performance.
Yuhao Li
Microsoft Community Technical Support