Right now the mig 23 series of air frames are overperforming is sustained turn rate. And I don’t know what you’re talking about, it can do 8gs just fine at around 400/750ish knots/kph
It can sustain 8g’s is different. A Max wing loading of 8.5g’s would be a continuous G force. When going into a turn a wing can sustain allot more Initially which is not modelled.