Just curious, could you point me to said QA session if it's a video or something? I'm not aware of such a limitation. You can use DLT's live streaming tables anywhere in the Medallion architecture, just make sure not to break stream composability by using Materliazed Views, probably in the Golden Layer if update/merge/delete is required.

I'm asking because I recently completed Fundamental/Advanced DE certification and I'm currently working on the Professional certification. Either I was a sleep (those videos aren't my favorite medium) or I simply never heard of this recommendation in training...