Would a Samsung Galaxy S9 with /e/ installed be susceptible to this security flaw?

[dln949]

https://www.vice.com/en/article/4avnan/bombshell-report-finds-phone-network-encryption-was-deliberately-weakened

[newts]

I believe this is implemented in the radio and not Android so, yes.

As explained in the article it is very rare fallback in certain places and not likely to be used.

Also if you are a person of interest to the kind of people who can intercept and decode your phone calls then you shouldn’t be using any phone.