Do short rate models actually have many practical applications within the average life insurer?

The UK life insurer I work at doesn't implement any short rate models within any processes (that I am aware of).

For calculating the interest rate SCR, a stochastic approach based on PCA is used (with 3 PCs being stressed to a 1-in-x level). For assessing liquidity risk and the sensitivity of the balance sheet to interest rates, prescribed stresses are applied to the observable yield curve. To hedge our interest rate exposure, bonds and swaps are used (we do not use swaptions).

I'm therefore curious as to why an insurer would use a short rate model as, in my experience, the approach used seems sufficient.

From a risk-management point of view, could anyone explain to me where a more complex short rate model would offer some benefit over applying prescribed stresses to the yield curve?