Seems like the seeds look quite different from Prunus dulcis and Prunus amara (I don't know if they are both wild types?). The bitter taste of the toxic version may have been an obvious sign to avoid them.
I wouldn't argue the point one way or another from the info I have read.
At least potatoes were on another continent and we know Grok couldn't eat them!
The "Seven Deadly Sins"
• Grains (wheat/rice/oats etc) . . . . . • Dairy (milk/yogurt/butter/cheese etc) . . . . .• Nightshades (peppers/tomato/eggplant etc)
• Tubers (potato/arrowroot etc) . . . • Modernly palatable (cashews/olives etc) . . . • Refined foods (salt/sugars etc )
• Legumes (soy/beans/peas etc)