By the way I still have no idea how to fix it…

I found something that's very interesting: my Simulator was using French as its primary language. I I put English as the primary language, the problem goes away 🤩

Even after 4 years of using Swift daily, I had never seen Decimal. Thank you 🙏🏻

I did not post it here, but I found a workaround. Let me know if it fixes your issue.