Why is this an issue?

Redundant Boolean literals should be removed from expressions to improve readability.

Noncompliant code example

If BooleanMethod() = True Then ' Noncompliant
  ' ...
End If
If BooleanMethod() = False Then ' Noncompliant
  ' ...
End If
If BooleanMethod() OrElse False Then ' Noncompliant
  ' ...
End If
DoSomething(Not False) ' Noncompliant
DoSomething(BooleanMethod() = True) ' Noncompliant

Dim booleanVariable = If(BooleanMethod(), True, False) ' Noncompliant
booleanVariable = If(BooleanMethod(), True, exp) ' Noncompliant
booleanVariable = If(BooleanMethod(), False, exp) ' Noncompliant
booleanVariable = If(BooleanMethod(), exp, True) ' Noncompliant
booleanVariable = If(BooleanMethod(), exp, False) ' Noncompliant

Compliant solution

If BooleanMethod() Then
  ' ...
End If
If Not BooleanMethod() Then
  ' ...
End If
If BooleanMethod() Then
  ' ...
End If
DoSomething(True)
DoSomething(BooleanMethod())

Dim booleanVariable = BooleanMethod()
booleanVariable = BooleanMethod() OrElse exp
booleanVariable = Not BooleanMethod() AndAlso exp
booleanVariable = Not BooleanMethod() OrElse exp
booleanVariable = BooleanMethod() AndAlso exp