Not only has it not been an issue...Tesla's share of plug-in sales has been increasing dramatically year over year.
Cadillac ELR, BMW i3, Chevy Volt, Chevy Bolt were all billed and hyped as "Tesla Killers" upon launch.
https://insideevs.com/monthly-plug-in-sales-scorecard/
To date, no other manufacture has announced any plans to procure enough battery supply to produce cars in comparable volume to Tesla.