The real world begs to differ: https://www.livescience.com/technology/electric-vehicles/china-puts-a-sodium-ion-battery-into-an-ev-for-the-first-time-it-can-drive-248-miles-on-a-single-charge

In the end it's a matter of price, reliability, usability, etc.
And while sodium based batteries have a worse energy density (space and weight wise) than lithium based batteries, they seem to have advantages in other areas (eg. no. of charge cycles, price per kWh, no thermal runaway, basically unlimited amounts of cheap sodium available).