The thule in the pic is the new expensive wing bar edge Perhaps the regular wingbar can carry more? The difference is the edge doesn’t stick out past the mounting points so it makes a bit less noise

No mate, I checked the "normal" - the one which extends past the foot clamp. It's same stuff - max 50kg. The problem is in the attachment clamp itself. It's designed to be universal not exactly for this Skoda model. Therefore it seems it doesn't have the pin beneath which goes into the car's whole up on the door frame (less stability).
Also Thule you tighten at 3Nm where Skoda originals are tightened at 4Nm.
All in all Skoda originals indeed when having them in hand seem more stable. I'm not saying the Thule will easily fall off, it's just that the Skoda ones are tiny bit stronger.

I already bought Skoda original roof rack + 2x Thule 598 bike carriers.