Tony deserves it, that's it.
"Who deserves it besides Tony" is kind of a moot point at the moment, given that Khabib and Tony are going to fight this spring.
In a normal division, whenever there is no clear contender, you make title eliminators until a clear contender emerge. So Conor and Justin should fight to determine the next #1 spot. There are also going to be several fights with title implications at LW (e.g., Hooker vs Felder, Lee vs DoBronx), Poirier returning etc. We also need to see how the Khabib and Tony fight goes. For example, if it is very competitive as we hope it will, that could be ground for an immediate rematch given that Khabib and Conor was completely one-sided.
In short, the LW landscape in a few months is what matter, and it might be quite different from today.