variable "multi_az_enabled" must have type boolean - not string

[disparo13]

What is the current behavior?
Just checked the variables.tf,

variable "multi_az_enabled" {
  type        = string
  description = "Specifies whether to enable Multi-AZ Support for the replication group. If true, `automatic_failover_enabled` must also be enabled. Defaults to false."
  default     = false
}

If its variables value assumed to be true or false - why type "string" then?

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem.
Open the variables.tf and find the record

What is the expected behavior?
The variable has a correct type.

Software versions?
3.2.0