[Nick Koan]

In other words,

Subaru *could* make the current multi-link suspension as durable as the mcstruts of old. There is nothing inherent in the geometry (in general) that makes the suspension more prone to failures.

Now, what we can now argue about is Subaru's specific implementation and manufacturing processes. Subaru took trade offs to gain cargo space, save weight, and still perform well under normal (street driving) circumstances. And from your experience Alex, you show that the WRX multi-link rear suspension is weaker, but that doesn't necessarily mean going back to mcstruts will make things stronger or more durable for racing. It could, but that really depends more on the specific mcstrut and all the other considerations and trade-offs Subaru would make for the new part.