One of the most magical and cost efficient characteristics of sourdough is how well the bread keeps. Never have I had to give the loaf of bread a once-over to check to any mold.
The most processed a sourdough bread is the weaker it becomes. The fun in sourdough is how consistently inconsistent your bread will be…but not in a bad way. Every variable possible can impact and impart flavor. Make the “same” loaf on days where the temperature is different? Different flavor.
That inconsistency is not favorable for mass produced bread. Those companies want the same loaf every time. They rely less on the natural bacteria that makes sourdough unique and instead use additives like citric acid to create a more uniform sour flavor.
Natural yeast and the bacteria they release are naturally preserve the bread. Will it keep for months? No, of course not but it will be just fine for 7-10 days left at room temp.