Inflation is a backward-looking measure. It doesn’t ease the cost of living, it simply lets policymakers know what’s going on with prices — and whether the Bank of England is doing its job.

On a personal level, you already know what your living costs are, so the level of the CPI has no relevance to your life. Nobody experiences CPI directly, as we all have different costs and preferences.

Firstly, inflation decreasing is a decrease in the rate of increase so it's never going to ease your cost of living. Your cost of living is still going up, just not as fast. Inflation is the derivative of the cost of living - the rate of change. (Similarly, the deficit is not the debt, the national deficit is the rate of change so a decrease in the deficit means that borrowing is still going up, just not as fast).

Inflation literally is "too much money chasing too few goods". Price gouging can only happen when there's not enough supply of something compared to the amount of people willing to pay for it. If there were more rental properties available than there were tenants looking to rent, then a landlord can't just go "I think I'll just double my rent to make more money" because no one would rent their property as there are others available. If on the other hand there are more tenants than there are properties (too much money chasing too few goods) a landlord can increase prices.