There's a similar issue on reddit. For a growing sub (which most interesting subs are) sorting by top of all time and top of this year is the same thing. I wish there were a way to sort by top by year on a sub (and HN too of course).
Might be interesting to plot the number of new posts per day over the years as well, if that data is accessible. I would guess it would inflate at the same rate.
After a year or two "most popular" no longer means much for those sites.
Which tends to directly clash with the temporal rat-race design used to keep customer eyeballs glued to apps for 100% of the day.