Finder -> Preferences -> Advanced: "When performing a search:" you can choose from "Search the Current Folder" (my current setting) or "Search This Mac" (apparently yours) or "Use the Previous Search Scope"
So, I'm nearly certain that I've not touched that setting, so the default is then "This Mac", which again, is what the parent is pointing out.
Without saying that the parent is right, that you've customized your setting does not invalidate the point the parent is making: that it is a bad default. (In fact, your customization might be proof towards it being a bad default.)
I didn't think I'd changed my default either, but I remembered I did run a shell script to set up "MacOS for developers" when I first got it, so maybe that was an included change.
I think all that demonstrates is that the default is bad for you and me. My parents use Macs, and I've watched my mother work enough to know she relies on the "This Mac" behavior regularly. She is a teacher, not a developer.
