I wouldn't say the Smiths speak to me any less now then they did when I was a teenager. If anything, rather the opposite.
People tend to relate to lyrics in an unneccessarily personal way. For my part I find that you tend to miss most of what a lyric has to offer if you go into it listening to it as if it was a comment to your own life and your own existence - it isn't. It is something far more interesting, namely somebody else's, transmuted into a form that is generally accessible. It gives you something that is beyond your own experience, which is a shame to waste just to get something as banal as a confirmation that you are who you thought you were. If anything, the incessant urge to approach the lyrics personally trivialises them, by tending to transform everything into some sort of external comment on states and phenomena already familiar. What happens to fit you can be used in a way that does not really offer anything you didn't already know, what doesn't is discarded or ignored - it's an intrinsically stupefying way to approach them. I don't understand why almost everybody seems to take it for granted that this is nevertheless the only way to listen to them.
Approach the Smiths era lyrics as something that has nothing to do with you or your life (that is in the very specific sense of "you or your life" - rather, they have a lot to tell anyone), and what you'll find is that all kinds of new and unexpected vistas and twists and turns open up. There's so much there to appreciate and love. The humour, the wit, the characters, the attitude. The marvellous microcosm of Rusholme Ruffians (a lyric the appreciation of which any previous personal strong memories of fairs can only obstruct) - arguably a more than decent stab at accomplishing within a 3-minute pop song something not too different from what John Dos Passos did in 500 pages in Manhattan Transfer. Or the very nearly nauseating indeterminacy of The Hand That Rocks the Cradle. The almost biblical punch of a line like See how words as old as sin fit me like a glove. The way melody practically grows out of words like but fresh-lilaced moorland fields cannot hide the stolid stench of death (try saying that line out loud without breaking into melody of some sort: You will find it is almost impossible).
Sure the Smiths felt like it addressed me uniquely when I was 16. But that was because I was 16. Nearly everything that mattered to me felt that way - you're hard-wired to focus in that direction at that age. It doesn't in the same way now because I'm a different person, of course. But what I heard then was not what the Smiths were about, it was just what I was capable of absorbing at that time. And there's more. Plenty of it. Embrace the fact that the music doesn't reach you in the same way anymore as an advantage - the unleashing of great art from the fetters of your sordid teenage existence. It never was about you. And these lyrics are much to be good to be wasted on mere self-recognition.