It doesn't matter if the inflation rate is zero, because UK state pensions are currently guaranteed a minimum of 2.5% increase per year. (So called "triple lock": you're guaranteed the highest of 2.5%, inflation, or earnings growth).
In fact due to earnings growth the projected adjustment for next year will be 2.9% even though the UK is facing negative inflation.
Also, other than expats who left early, almost all UK retiring pilots should qualify for the 6,000 GBP as that is only the basic pension. The UK currently has a two-tier pension system.
If you opt out under a company pension, you are opting out from the "Additional State Pension" -- under various schemes -- which is above and beyond the basic pension.
So most who work in the UK until they retire should in fact receive more than the basic 6,000 GBP as they'll have at least some amount of Additional State Pension for the years they did not contracted out.
(At least until next year, when the UK system will be revamped).
The blessing for UK pilots retired in Canada recently has been the favorable exchange rate due to the weak Canadian dollars. However this followed many years where the GBP was declining vs. CAD.