Wrong information.
We planted an oak tree in my front yard in 1979 and it has been producing acorns for more than ten years.
I don't know where you pick up this bit of information, but it is not accurate.
*****I don’t know where you pick up this bit of information, but it is not accurate.*****
A dear friend sends me interesting emails which provoke research and discussion - helps educate!!
OK;)
https://www.gardenguides.com/115030-acorns-oak-trees.html
Acorn production begins when the oak tree reaches 20 to 50 years of age. Production of acorns increases each year in proportion to the size of the oak tree’s canopy.