Honestly it didn’t even occur to me that this could be a problem somewhere in this day and age. I don’t even remember when was the last time my bank sent me an SMS for MFA, but it’s a good point for people in US.

I’m not an expert in this field, so other people might have something else to add, but my takeaway is mostly - do not rely on phone services. Don’t use MFA via SMS, etc. Most of the issues described, you can avoid if you’re careful, except the geolocation issue.