We can't fairly or accurately write a history of the earliest reception to the news that penicillium excrement might save human lives, if we credit the scientists of the 1920s and 1930s with all the hindsights that scientists and the public hold today about the best place to find new antibiotics.
Because in those heady early days of the discovery that metabolic activities can be usefully divided into essential-to-life primary metabolic activity and unknown-uses secondary metabolic activity, the metaphor most scientists reached for to explain the secondary metabolites of the lower fungus was of the well known plant and animal need to excrete unneeded and potentially deadly 'metabolic waste'.
Poo and pee and go-go and caca in daycare talk.
Would you, even today, instantly let your doctor to inject poo and pee into your blood stream when asked, without hesitation and discomfort ?
Let alone way back in the Era of (Man-centred) Progress, where it seemed impossible to believe anything a stupid simple little fungi cell could do might be superior to what advanced civilization's best chemical laboratories could invent.
Progress 1945 (upended) : primitive penicillium poo saving more kids than advanced civilization could bomb or gas.....