Everyone has a different set of moral codes. Some think it's OK to lie and claim to be living in the UK, so that they can get state pension increases. Up to you as they say - your decision.
For me, I was taught by my parents to never lie, even if the truth hurts me or others. So there is no way that I would lie and claim to be living in the UK. I do have a registered address in the UK, (registered with the electoral register, GP, bank etc etc), but I am not Ordinarily Resident.
I know the rules regarding frozen UK pensions, and have no intention of breaking those rules by lying. If my modest UK pension is too little for my needs in future years, then I'll simply relocate and live in the PI, where my UK state pension is aligned with pension increases applied in the UK. But for now, I don't need to consider such a move.