It's difficult to say if the PS5 will be on discount for Black Friday. Most signs however point to "no." The PS5 is in high demand having just been released. Most stores unfortunately don't have the items in stock to keep pace. The only surefire way to get a PS5 by Black Friday is to go into stores like Walmart, GameStop, or Best Buy now while they still have stock.
Add-ons and games however could see large discounts. Things like an extra PS5 controller, headphones, and a newly released game could be put on discount separately. It's also not out of the question to see these items paired together in a bundle with the PS5 console. It all depends on the inventory of each store.
The PlayStation store itself should have plenty of deals and discounts on games for both the PS5 and the PS4. However, the PS5 console itself might be hard to come by Nov. 27.