I think price gouging is a major part of all inflation we're seeing. Nothing "just" about it; it's the central problem. Corporate profits are at an all-time high, while prices rise and lots of people struggle to get by.
The only reason it's happening is because corporations think they can get away with it. There's not enough players on the market for someone to be willing to compete on price; it's all one giant cartel.
I believe price gouging is behind most of the inflation we’ve encountered the last couple years. Companies reduced the workforce, forced the remaining employees to maintain the same amount of production and increased prices. They then turned around and gushed to shareholders about their record profits.
I don't know about cereal manufacturers specifically, but in general, it costs 25% more now compared to pre-Covid to produce food[0].
The amount Americans spend on food relative to their income has gone up in that same time period, but only from slightly under 10% to slightly under 12%[1], and is still well under historical levels as well as compared to other countries. Not bad for an economic system full of supposed "price gougers".
[0]: https://fred.stlouisfed.org/series/PCU311311
[1]: https://www.ers.usda.gov/data-products/chart-gallery/gallery...
I've seen a similar price increase in the branded cereals, so I am not disagreeing with you in that sense.
--------
However, the store brand cereals, which are cheaper, haven't really gone up at all. At this point the branded product is more than double the unit cost of the store/no-name brand version in my local stores.
This suggests to me that it's not an actual increase in the cost of producing the product. If it was driven by commodity/input/manufacturing cost prices we should be seeing price pressures coming through in the cheapest cereals.