“Hope makes a good breakfast. Eat plenty of it.”

Introductio ad prudentiam: Part II (1727), Gnomologia (1732)

According to The Quote Investigator, this phrase first appeared on PIMA’s North American Papermaker: The Official Publication of the Paper Industry Management Association, in an article by Bill Moore and Jerry Rose. The year was 2000. Since then, the phrase has appeared many times. Peter Drucker died in 2005. The first time his name was associated to the citation was on 2011. Other occurrences and versions of the phrase can be found at https://quoteinvestigator.com/2017/05/23/culture-eats/
Misattributed

Source: Iced

Quoted in Somerset Maugham (1980) by Ted Morgan

In conversation with Max Brod (1920), after Brod had queried on there being "hope outside this manifestation of the world that we know", as quoted in Franz Kafka: A Biography [Franz Kafka, eine Biographie] (1937) by Max Brod, as translated by G. Humphreys Roberts and Richard Winston (1947; 1960); at least as early as Franz Kafka : Parable and Paradox (1962) by Heinz Politzer, this assertion has often appeared paraphrased as: "There is hope, but not for us", and sometimes "There is hope — only not for us."
Variant translations:
Oh, plenty of hope, an infinite amount of hope — but not for us.
As translated in Weimar Intellectuals and the Threat of Modernity (1988) by Dagmar Barnouw, p. 187

Source: To All the Boys I've Loved Before

Source: Fool

Classical Japanese Database, Translation #174 http://carlsensei.com/classical/index.php/translation/view/174 (Translation: Reginald Horace Blyth)
Individual poems
Original: (ja) 朝顔に
我は飯食ふ
男かな
Original: (ja) asagao ni
ware wa meshi kû
otoko kana