Yeah, Billie Jean is a good line but the bass has very little to do with people liking that record as far as I can tell.
Here's what wikipedia says:
The song is well known for its distinctive bass line and Jackson's vocal hiccups.
. Bass guitarist Louis Johnson was then brought in and he played his part on every guitar he owned, before Jackson finally settled for a Yamaha bass.
After four bars, a repetitive bass line enters. It never rests for more than an eighth note and centers on a seventh. Each time it passes through the tonic, the note is doubled by a distorted synth bass, played in unison with a shaker.
According to Daryl Hall, when Jackson was recording “We Are the World,” Jackson approached him and admitted to lifting the bass line for "Billie Jean" from a Hall and Oates song (apparently referring to Hall’s "I Can't Go For That (No Can Do)" from the 1981 album Private Eyes): "Michael Jackson once said directly to me that he hoped I didn't mind that he copped that groove." Hall says he told Jackson that he had lifted the bass line himself, remarking, "it's something we all do
presenter Zoe Ball said, "I'm delighted that 'Billie Jean' has been voted the greatest dance record ever made. This is Jackson at his best." She continued, "This track is way up there for me - Jackson's rendition of it at the Motown 25th anniversary show has got to be one of the great live performances of all time. The bass line is awesome, the production is killer. It's just perfect." In a list compiled by Rolling Stone and MTV in 2000, the song was ranked as the sixth greatest pop song since 1963
In an interview, R&B artist Pharrell Williams stated that "Billie Jean" was one of his favorite songs. "It is hard to say if there is a greater song than 'Billie Jean'. I think there will never be a song like this one again, with this bass line, with this kind of effect, this eternalness, this perfection