The white line issue on my S21 FE began after the May 30 update. This problem isn’t limited to the S21 FE—it affects many Samsung-supplied AMOLED screens, possibly from a defective batch also sold to other brands, including Apple. A service center representative first informed me of this.
If you face this issue, escalate it promptly via email and the customer care helpline. Always keep a receipt from an authorized service center as proof for any escalation and as evidence that you reported the problem.
