This is such an important point. So much of inflation is not $THING used to cost $X and now costs $Y, but that $THING is significantly lower quality than it used to be. Quality is famously difficult to quantify (Pirsig), so it is much easier to manipulate it without people noticing. A product that looks the same, but is slightly worse, at purchase time is a lot harder to identify than the same product that costs 20% more, so businesses prefer it.

That happens incrementally over years, until the product is a shadow of its former self.