That is not a good analogy for comparison because there's not a finite amount of goals a player or team can score like there is with points in a league system.
As stated previously, league position is a far better way to judge progress. That's not to say points is not a metric you can use, but it's not as clear cut. If we were talking about the difference between finishing 1st and any other position, do you think anyone would give a toss about the points total?
But this didn't happen, and we finished above both. Of course if it did happen and we finished 5th, it is still a place higher than the previous season and you can judge that how you wish.
We went from having a very bad first half of the season to a good second half, which was progress in itself. It's an upward trajectory, which we have continued this season.
Well, obviously, but by comparing a player's or a team's performance on the basis of everyone's performance but the team or player itself you're going to tie yourself in knots, trying to make arguments that can never be proven.
For example, some people will say that a league where one or two teams get close to a hundred points isn't competitive, as if the competitiveness of a league is made up by 10% of the teams. On the other hand, some people will say that the Leicester season, where the winning team got a low points total, and thus had teams more tightly compressed, was the worst season in terms of competitiveness as all potential title challengers had shit seasons. Which one of the two is right is impossible to know and is just a matter of opinion. It's the same with goalscoring. If Martial scores 20 goals last season and 5 goals this season, my opinion would be that it's Martial who's having a shit season, not defences all across the Premier League improving (and specifically against him!).
What is possible to know is how good a team is at beating the opponents in front of them, and that is by seeing how many points they get at the end of a season.
United's improved form post lockdown is obvious from the fact that United had an average of 2.33 points per game and Leicester's decline is obvious from the fact that they dropped to a 1 ppg ratio post lockdown. What United did is irrelevant to my opinion of Leicester's performance level (ie I wouldn't have thought that Leicester had been on the same level post-lockdown if they'd managed to end in 3rd place anyway), and what Leicester did is irrelevant to my opinion of United's performance level (our improvement post lockdown would've been visible even if we hadn't made 3rd).
So, in essence, I think that the performance level of the team (or player) itself is much better to judge the team (or player) by than the performance of everyone
but the player or team that is being judged, because the relative performance level brings so many unknowns into play. Did Martial not score because Ben Mee had a stormer? Should de Gea be kept in the game because the WBA player had a particularly good game with his crossing? Should we avoid criticising AWB's attacking because their left back had a good game? I mean, relative performance levels makes it so that every poor (or good) performance can be explained away by other factors.