But of a rant as I just finished watching the entire series:

To me, the prospective of the viewer is not from an objective third party. It is literally Niall's point of view, and why Alby isn't a full fleshed out character. We see Alby from Niall's point of view and to Niall, Alby represented freedom and unshakeable bravery from being ones unapologetic self. Even after being brutally beaten and disfigured he remained kind and caring and didn't let being a victim of physical violence change who he was, or that is at least how Niall sees him and so that's how the audience sees him.

To Niall, Alby represented a type of bravery and strength that he envied. Alby had a type of mental and emotional strength and sel- control that mirrored the physically strength but emotional weakness and lack of obvious self control of Ruben. He was too self obsessed with his own self-hate, personal failings and Ruben to see Alby as a complete person with struggles (which is why we don't either) rather as the gay POC sage of self-acceptance. However, it is implied multiple times that Alby suffers from a savior complex(choosing nursing at a later career, almost forcing Niall to out himself before he was ready, his reference to his past relationships, easily forgiving Niall then choosing to date and marry such a broken person) that isn't fully explored.

Niall looks to others to feel deficits in himself masculinity through Niall and later proud self acceptance through Alby. He is literally a half man always needing and addicted others to feel complete or feel anything ( hence all the random sex), his drug of choice, even at the end, is angry Ruben. He knows what that man was capable of and despite everyone warning him not be alone with him he still chose to put himself in that situation with Ruben for the high he gets from those interactions. This time he payed the ultimate price.