If the Conrad still maintains some sort of beach access for guests, it's a mystery to me -- we asked the staff about recreational opportunities in the area, and it wasn't mentioned. I was actually a bit surprised by their lack of knowledge. We then went online and figured out by ourselves how to access the well-known Knysna forest areas north of town (which are certainly worth a visit if you're in the area, but are not spectacular).
In general these same online resources told us that while Knysna is considered to be a very pleasant town, it is not known for its beaches. If you want a "beach vacation," you generally stay elsewhere along the Garden Route.
I am sorry if I offended you by my comment about running into pretentious guests, but that was our experience at the Pezula. South Africa is a very unique country: there's basically a fairly affluent European country nestled within an African country. The existing income disparities are somewhat astonishing: whites earn about 5 times what blacks earn. That may not be good for South African society, but for foreign visitors it's not necessarily a bad thing: the affluence of the mostly (but not exclusively) white population creates a first-world infrastructure that enables visitors to very comfortably explore a country very different from their own. In most developing countries, all the nice restaurants and hotels and attractions are mostly for foreigners: in South Africa, there's a large segment of the local population that is enjoying these facilities as well. For example, you can travel to South African national parks and share them with the locals.
But the Conrad Pezula is so freakin' expensive that even the vast majority of affluent South Africans could not afford to stay there. So their clientele is almost exclusively foreigners. Very rich foreigners. The type of people who hire drivers because they think it's too dangerous to drive themselves around, or the kind of people who wouldn't dream of staying in a SanParks safari camp and would only stay at luxury private camps (where they will only encounter other extremely rich foreign visitors). Given that I think the "magic" of South Africa IS interacting with the locals -- who tend to be extremely friendly and helpful to us folks from "away" -- you can probably understand why I think some of the Pezula guests are a bit pretentious. Your mileage may vary.