You are correct - I moved and thought the store in the new area was a ripoff before realizing that food prices are up everywhere. I buy a fair amount of Indian groceries and the prices of many staples is up ~25-30%.

Real prices lag behind deflation. Short term deflation is really only visible in market/financial metrics/prices.

But your other point is probably more correct - supply/demand swings in the short term affect the prices you see more than deflation/inflation.

Technically a gallon of milk should go up in price like 6-10 cents a year, which you might not notice.

Some food products have increased in price since the pandemic mostly due to production and distribution chain issues. However, the basic staples you mention are such a small proportion of the budgets of people that even a significant rise in their price won’t move the inflation needle much compared to other categories.

Oil/Gasoline went down in price early this year quite dramatically. This (as energy cost) is included with a heavy weight in the price index calculation.

You need to consider the whole basket that the CPI is based on including other factors like housing, utilities, and oil/gas. We probably won't see any specific store bought items drop in price but trends overall will reflect deflation. Part of that is the cash injection is not spread over just the US population but anyone that relies on the USD for transactions or backing their currency. Being the default currency has perks.

I have experienced what you have -- food is about the same or more expensive than before. But the housing market has softened. Retail goods in stores are much cheaper. Clothing is incredibly cheap -- go to an outlet store and you'll see 50% sales everywhere.

Plenty of products aren't lowering in price, but are getting you more quality for the same price, e.g. a faster CPU or more RAM in your smart phone. Economists consider that a price drop for the calculation of inflation.

That's technically correct, though of course does not feel like it for many people. To the average consumer, a "phone that can play today's games" is the same measurement today as it is next year, and if prices don't change, they might not consider that "quality increase".

Food and oil prices are volatile and can mask inflationary and deflationary periods, which is why I linked to the consumer price index minus food and energy as that is more accurate.