Last we knew, Sony still manufactures the PS4, two years after the release of the PS5. This is the way things have been for a long time, with cost-reduced slim versions of the last-gen console sticking around until prices for the next-gen console finally drop enough that demand for the last-gen console dies out.
However, the success of the Series S provides an alternative option, and I see no good reason for Sony not to follow suit next-gen. I think everyone benefits from the two-SKU strategy, as backwards compatibility paired with a budget next-gen console will allow for the previous-gen to be more quickly retired. Developers win if it cuts a year or two off of the necessity of maintaining cross-gen support. Consumers on a budget benefit by getting a console built upon the new and more efficient architecture (look at how Series S approximately as powerful as the One X, yet smaller and cheaper, due to the huge architectural improvements). Sony benefits from the fact that having a regular and a Pro version at launch will help them get a lot more units produced from day 1, and will move consumers to the new architecture more quickly.
In fact, Sony started this two-SKU trend with the PS4 Pro, so they're obviously not averse to it. And PC games have been scalable to different levels for decades now. The main innovation with the Series S was leading with two-SKUs at the beginning of a generation.
Microsoft ended Xbox One production as soon as Xbox Series manufacturing began. In a perfect world, I think Sony would prefer all their system sales going towards a next-gen architecture too, not still producing last-gen consoles two years into this generation (and counting). so I've got to believe they'll be at least doing their due diligence on this option next time around.
I predict that there won't be a PS5 Pro. Instead, now that we're in a period where architectural improvements are the main way forward for more performance and efficiency, I think that Sony will introduce two new PS6 SKUs right off the bat next-gen, both on a new and more efficient architecture. One will be approximately as powerful as a PS5 Pro might have been. The other will be a "Pro" console launched right at the beginning of the generation that will be the true successor to the PS5. Both will use the same architecture and it will just be a matter of scaling the fidelity up and down.
TLDR; I predict there won't be a PS5 Pro, and that we'll instead get a PS6 and a PS6 Pro right off the bat next-gen.