I'm guessing it probably was, it dovetails nicely with the opening shot of the season with he and Abby looking up at it.
The 2019 scene was a decent epilogue, but I had kind of wished it just ended with Paul walking away with his limp, a perfect analogy for the period of New York covered by The Deuce. The ending felt quite put upon, but I enjoyed it as a stand alone. And to be fair, it works nicely with the scene of Vincent noticing how empty Leon's has become.
It was very good to see all the old faces one last time, as was the case for Vincent I think. If I read into it all the faces he sees were dead. The paper confirms Eileen, Bobby confirms himself, I think we can safely assume Paul succumed to HIV, and Detective Ralph Macchio likely drank himself to death, or died while "cleaning his service piece" during his time at the academy, and Leon was pretty up there in age and looking slow during the last diner scene
That leaves Joey, who we know is getting married (for the third time), Abby (who we see), and Alston (who we don't) for the folks Vincent regularly interacted with. I like to think Alston is retired and happy. Abby also looks exceptional for what would be approximately 60.
That last one makes me wonder why they fast forwarded all the way to 2019. You could have gone to 2012, not changed much about the setting, and still had Abby a spritely early 50s.
Yup, I had to look this up afterward myself. I guess Nathan was, according to Simon, the loose inspiration for Avon. Nathan felt it was a little more than loose. I'm sure this is Simon poking the bear a bit.