From Wikipedia (quoting part of one section):
Definition of Yacht Rock
The term “yacht rock” did not exist contemporaneously with the music the term describes,[6] from about 1975 to 1984.[7][8] It refers to “adult-oriented rock”[6] (or “West Coast Sound”)[4][3] which became identified with yacht rock in 2005, when the term was coined in J. D. Ryznar et al.'s online video series of the same name.[9][10][11] Understood as a pejorative term,[6] “yacht rock” referred, in part, to a stereotypical yuppie yacht owner enjoying smooth music while sailing. Many “yacht rockers” included nautical references in their lyrics, videos, and album artwork, exemplified by Christopher Cross’s anthemic track, “Sailing” (1979).[12] Long mocked for “its saccharine sincerity and garish fashion”, the original stigma attached to the music has lessened since about 2015.[6][3]
In 2014 AllMusic’s Matt Colier identified the “key defining rules of the genre” as follows:
“keep it smooth, even when it grooves, with more emphasis on the melody than on the beat”
“keep the emotions light, even when the sentiment turns sad (as is so often the case in the world of the sensitive yacht-rocksman)”
“always keep it catchy, no matter how modest or deeply buried in the tracklist the tune happens to be.”[7]
The “exhilaration of escape” is “essential to yacht”, according to journalist and documentary-film maker Katie Puckrik. She quoted the lyrics of Cross’s “Ride Like the Wind” (1979), “to make it to the border of Mexico”, as an example of the aspirational longing that demonstrates “the power of the genre”. Thwarted desire is another key element that counters the “feelgood bounce” of yacht in the same song. Puckrik identified a sub-genre, “dark yacht”, exemplified in Joni Mitchell’s “accidental yacht rock” song “The Hissing of the Summer Lawns” (1975), which described the “tarnished love” of “a woman trapped in a big house and a loveless marriage”.[13]
According to Mara Schwartz Kuge, who worked in the LA music industry for two decades, “Soft rock was a genre of very popular pop music from the '70s and early '80s, characterized by soft, mostly acoustic guitars and slow-to-mid tempos … most people have generalized the term to mean anything kind of soft-and-‘70s-ish, including artists like Rupert Holmes. Not all yacht rock is soft, either: Toto’s ‘Hold the Line’ and Kenny Loggins’ ‘Footloose’ are both very yacht rock but not soft rock.”[14]
Comprehensively defining yacht rock remains difficult, despite agreement that its central elements are “aspirational but not luxurious, jaunty but lonely, pained but polished”. Journalist Jack Seale stated that, as in other “micro-genres”, certain albums of artists who are accepted as proponents are “arbitrarily ruled in or out”. For example, Michael Jackson’s Thriller (1982) is accepted as yacht rock, but Fleetwood Mac’s Rumours (1977) is not.[15]