FWIW, I remember the sea shanties being wildly popular in the Assassin's Creed gaming community when they got introduced in AC Black Flag (or was it AC Rogue?) and they have been added to every following game that features sea travel.
Seems to be aligned with the current Zeitgeist.
The tune is designed to carry itself without musical accompaniment, has limited range, and is easy to harmonize with. The coarse lyrics about various hardships and simple tune almost lend itself to voices that aren't particularly sweet, and that gives it a charming character of it's own.
Now, given that people have been quarantined for months on end, sea shanties are a drop in for a want for community.
It was quite a few years ago - but perhaps it was the spark.