PS5 will be 499. Get it out of your head that it will be lower. Sony needs to take no precautionary steps.
I can't imagine there being very many people predicting otherwise for the model with a disc drive, so not sure who you're aiming this at. The discless one on the other hand will be cheaper - the only question is by how much. At this point, anything over 399 is just going to kill the discless version, but bringing it down to 299 or even 349 sounds like a big sacrifice of profits (at least in the short term - in the long term, increased sales of digital games might make up for it).