It's 23 years old because it's been a known exception to pythag for a long time. Which part doesn't make sense?
And I wouldn't say there's no conclusions. The highlights are as follows:
Teams with good bullpens actually won more games–about 1.3 more, on average–than would be expected from their totals of runs and runs allowed, while teams with bad bullpens won about 1.6 fewer games than expected....
When we combine the results of both one- and two-run contests, teams with good bullpens win 0.47 games more than expected, while teams with bad bullpens win about 0.80 games less than expected. Together, this still explains less than half of the disparity between actual records and Pythagorean projections.
So while close games can't fully explain the divergence from pythag, the divergence from pythag - teams with extreme bullpens over- or under-performing - certainly exists.
I would be wary of tossing out blowouts like the reddit post does because a pretty basic premise of pythag is that blowouts reflect true talent moreso than the binary wins and losses that result from them.