There is no valid ethical defense for using an "index of" link for Peaky Blinders Season 6. The show is legally available on (UK), Netflix (International), and various VOD platforms. By using an index, you aren't "sticking it to the man"; you are risking your digital security for a substandard viewing experience.
The final season consists of six episodes, originally aired on BBC One and later released on Netflix : Index Of Peaky Blinders Season 6
The "Index Of" method is essentially the digital equivalent of looking for a VHS tape in a dumpster. You might find it, but it will be dirty and probably broken. There is no valid ethical defense for using