Can you please explain how the puratos lab

Yeah, I can explain that:

"... refreshed every two months with the original flour with which it was made, thereby replicating conditions in the original bakery."

https://www.questforsourdough.com/puratos-library

Funny, mh?

What does that have to do with bread?

Nothing, it means you don't have any idea how "that starter from etsy" smelled.

Starters contain the yeast that’s in the flour and the air where they are made.

Then you say: And maybe the defining variable is your local microbiota,

🙄 You really have issues reading, don't you.

lol that was the point I was disagreeing with then you flip flop or something.

My point was that a bought starter will change at your home, but since your own source shows that it is in fact the flour, you probably should go bake some bread. aY cArAmBa.