My point is to mitigate the risk of the immigration requirement if it’s asked.
Plus having cash is a necessary backup in an emergency.
As to your point, I would argue that your smart phone (with access to cash) is just as risky as cash as a target for theft. The “risk” is only moving from one node to the other.
With respect to phone numbers, I used Tello which gave me access to a US number and I could use the WiFi calling feature at any access point. You could also use it for 2FA. Much better than Google phone. I also used NordVPN so I could enjoy all my US streaming services. Amazon/HBO max/Disney etc.
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