These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Americans Hate Tingle: Once disco fell out of fashion, they became personas non gratis in the United States, even though they weren't recording disco songs anymore. For instance, their 1987 single "You Win Again" was a number one hit in ten different countries; its US peak was 75.
Angst Dissonance: Their songwriting in the early 1970s skewed heavily toward depressing, melancholy ballads. The record buying public, both in the UK and the US, became quickly tired of it and stopped buying their albums. It wasn't until they re-emerged as a dance-pop band that they became successful again.
"Rest Your Love on Me", written by Barry Gibb, was an obscure B-side for the Bee Gees. Conway Twitty covered it and took it to #1 on the country charts.
"More Than a Woman" is an odd case. The Bee Gees originated it for Saturday Night Fever but their rendition and a Cover Version by Tavares were both included on the soundtrack. Tavares released it as a single and it became a hit, but that take has long been forgotten and the Bee Gees version is the one you still hear.
Ear Worm: Notably "Stayin' Alive", "You Should Be Dancing" and "Jive Talkin'". Away from their disco period, try "Lonely Days", "I Started a Joke", "Massachusetts", and the chorus to their last single "Alone" if you want good earworm material.
Ensemble Darkhorse: Maurice has a large fanbase despite singing far and away the fewest lead vocals of the three brothers.
Just Here for Godzilla: A number of fans try to justify their love of the group by claiming that they only like the pre-disco stuff.
Misattributed Song: Samantha Sang's "Emotion" is often attributed to the Gibbs. They did write it and sing the chorus, though, so it's understandable.
Andy Gibb's songs also tend to be attributed to the Bee Gees. But like the Samantha Sang example, Barry usually had a hand in the production of them, so it's an understandable mistake. And Andy is the Bee Gees' brother, so it's not surprising he'd sound like them anyway. And then there are the people who don't make a distinction between Andy Gibb and the Bee Gees in the first place.
Which turns out to be very useful for CPR training as well.
Never Live It Down: Americans will never think of them as anything else than a disco phenomenon, no matter how what else they do and have done.
Older Than They Think: The Saturday Night Fever period was actually the Bee Gees' second wave of popularity. The first was actually as a Beatlesque rock group in the late 60s, which completely lacked both disco and the falsetto that would become their trademark. Listen to songs like "Massachusetts" and "To Love Somebody"; if all you know are the disco songs, you'll be surprised it's the same band.