What tyre size are you using as a 28 mm MIGHT have survived, but 25 kph into a square edge curb at a 45 degree angle is a BIG impact!
I think that some earlier photos I saw that the tyre is a gator skin, and if so, I don't think there is a tougher tyre!
Did spokes break, or did they pull through the rim as the wheel has a huge buckle!!!
A deeper > 30 mm and wider 25 mm to the brake surfaces rim, will be a lot stronger, but I do not know if even a rim like that, would survive this impact at 45 degrees!
I go for safety, so I would not go for a Carbon Fibre rim, as I THINK (but don't know) that one of these would have exploded with this impact!!!
I think I will get some vigorous replies!