I dunno. People put too much stock in Max Weber, who cherry-picked his evidence: he literally used Benjamin Franklin, a deist who'd abandoned Christian doctrine, as his model "Protestant." He created a compelling just-so story that is now picked up by people who never check the actual sources.
I mean, here are actual Calvin quotes:
> Nothing is more dangerous, than to be blinded by prosperity.
> Men are undoubtedly more in danger from prosperity than from adversity. for when matters go smoothly, they flatter themselves, and are intoxicated by their success.
> A man will be justified by faith when, excluded from righteousness of works, he by faith lays hold of the righteousness of Christ, and clothed in it, appears in the sight of God not as a sinner—but as righteous.
> Hence the Prophet reminds us, that though God would bountifully feed his Church, supply his people with food, and testify by external tokens his paternal love, and though also he would pour out his Spirit, (a token far more remarkable,) yet the faithful would continue to be distressed with many troubles; for God designs not to deal too delicately with his Church on earth; but when he gives tokens of his kindness he at the same time mingles some exercises for patience, lest the faithful should become self-indulgent or sleep on earthly blessings, but that they may ever seek higher things."
Anyways, it's probably good to let Actual Calvinists weigh on the matter:
https://www.desiringgod.org/articles/the-real-protestant-eth...
If you want to argue that this work ethic is a real phenomenon...sure. But I think you have to start with recognizing that the supposed exemplar was a person who generally unmoored from orthodox Protestantism, so "Protestant work ethic" is really a misnomer.