Yes, absolutely a deal breaker... but I carry two phones b/c I do not trust Verizon after being disconnected overseas. Their international plan requires you to re-connect to a US-based cell tower in order to "reactivate" the international plan if it has been disconnected. I am not aware of any service that allows me to buy an e-sim for any given random country airport and activate it before I reach the exit.
edit: forgot to add ... if you change countries or have to make an additional unplanned hop, VZ does not work in that scenario either.
edit: forgot to add ... if you change countries or have to make an additional unplanned hop, VZ does not work in that scenario either.