Ehh, I can see the two sides of the thing. The reality is that under the way that the ATP rankings were calculated in 1977, Vilas was never #1. To go back and change the way you calculate the thing in order to contrive an outcome seems a bit off to me.
On the other hand, if you look at the issue in historical context, Vilas’ failure to reach #1 doesn’t really matter. The ATP #1 means everything today, but back in the ‘70s things were very different. The only reason the rankings came about was to sort out who got entry to various tournaments. Nobody regarded the ATP #1 as being necessarily the best player in the world – including the ATP. There were a bunch of flaws in the system from that respect – not least the fact that ‘results averaging’ heavily penalised players (like Vilas) who chose to compete in a lot of tournaments.
Anybody who knows anything about tennis agrees that Vilas was the best player in the world in 1977 – if not across the whole season, then certainly for at least part of it. His failure to get to #1 in the ATP rankings is more an interesting piece of trivia than a slight on his achievements or ability.
Tennis is one of those sports where historical context is immensely important, and players need to be judged by the yardsticks of their own era rather than today’s. Otherwise we would all be saying Stan Wawrinka is a greater player than Pancho Gonzales because he has a higher Slam count.
ATP Rankings system was different back then and probably not that reliable though it gave Connors the opportunity to be no1 much longer
I don't think ATP will ever go back and update the system to re-write history so Vilas is granted the no1 spot. If the ATP updates his ranking points then other players will come out and question their official ranking.