This is a nonsense debate, really. The H1B is a non-immigrant visa but it's also dual intent so it allows you to pursue immigrant status.

https://global.temple.edu/isss/faculty-staff-and-researchers...

> The doctrine of H-1B dual intent has the following legal bases:

> Unlike many nonimmigrant categories, I.N.A. § 101(a)(15)(H)(i) contains no requirement of proving there is a "residence in a foreign country which he has no intention of abandoning;"

> The H category is specifically excluded from the I.N.A. § 214(b)'s presumption of immigrant intent;

You say:

> You're not supposed to rely on it to build a life in the US with no backup plan

when in fact the visa very specifically allows it (as per the "no intention of abandoning"). People arriving in the US on an H1B visa with immigrant intent are absolutely following the law. Is it a good idea? Much more debatable. But they're not acting without precedent nor without specific legal text allowing it.