The root cause is global competition, especially from countries with very low wages - Ukraine, a country in Europe, for example, was a top food supplier for Africa -, and widespread income disparity in many Western countries - 67% of Americans self-report to live from paycheck to paycheck [1], for example. First it's "luxuries" that get the cut - travel, eating out, entertainment - and once everything has been cut, people go for savings in food because that's the last large expenses block that they can meaningfully control.
[1] https://www.investopedia.com/living-paycheck-to-paycheck-you...
[2] https://www.boeckler.de/de/boeckler-impuls-vermoegen-nur-jed...