The Linked column may display ☆ to show that the associated track has an explicit Album Rating set in iTunes or Music.
The Apple applications can synthesize album or track ratings. How it works depends on the Album Rating value. When the album rating is not set, the application may synthesize the album rating based on the average of the album's track ratings. When a non zero album rating is set, iTunes and Music may display the same rating on tracks where there is no explicit rating. Visually the only way to know how it is currently working is by the colour of the stars. Grey/black stars represent synthesized values.
If you want to display accurate track ratings you have to reset the Album Rating to no stars.
Forcing the reset is controlled by the Settings - Apple Apps - General - When exporting clear Album Rating setting. This setting is applied for all exports to Apple Apps. This includes the UI, the Export to Apple App action statement and auto exports.
There are two possible values to the setting. Explicit will only reset the rating if Yate detects that the Apple App has an explicit rating. Explicit and Synthesized will reset the album rating every time an export is performed. This can potentially be slower as files in the Apple App which may not need to be touched are always processed. If Explicit works for you, use that setting. Music can synthesize album ratings at seemingly random times. Simply exiting and restarted the application can change the display. If you continue to see grey/black ratings, try the Explicit and Synthesized setting.
Note that prior to Yate v9.0, the setting was on the Auto Export settings panel and only supported Explicit.