Having just upgraded PS & LR to the latest November release (PS 23.0.1 & LrC 11.0.1) I would congratulate Adobe on the AI subject selection with one observation / complaint.
The AI does a great job of making appropriate selections in both modules. in LR the subsequent workflow is very logical and making edits to the mask for the areas where AI has not quite been perfect is easy using the menu tools.
However in PS the same excellent selection is made but the subsequent tools for adjusting the selection(s) are less user friendly. In fact it took several attempts before I realised that to make an adjustment you need to generate a layer mask for all the elements selected. There is no doubt that this approach "works" but it is less user friendly than the LR workflow. The ability to adjust the selection before it becomes a mask would, in my view, make this new feature perfect!
Perhaps the Adobe tech team could think about this for the next update or have I missed some part of the workflow which makes these comments redundant?