You said it: strong ties to their home country.
That’s not always the case. We left our home country more than a decade ago and have been living/working in different countries during this period. She got a job offer in the US and during the PERM process, she took an unpaid leave from her job. We have a couple of houses in the US so she came here and stay it as tourist until they approved the PERM and submitted the I-140/I-485. She went to the AOS interview and the officer didn’t ask much about it.
My case was a little bit different since I was working on rotating schedule all around Middle East. For me it had more sense the consular processing back then since I was working. That changed during COVID. So now I have a wife living in the US and with all the delays during the consular processing, that’s a “reason” to ask for AOS.
Now, that’s why your backstory is important. If you have a stable job, house and everything back home, yeah, you are right. But there are cases out there, like mine.