Sitcoms were originally an evolution of theatre, which meant that individual scenes were performed like a play in the studio with a real audience sitting in front of the setup — the fourth wall, so to speak. And the laughs you heard in the earliest sitcoms were genuine laughs from the audience sitting in the studio watching the live performance.
But as sitcoms moved away from theatre and into the realm of TV, the actors started doing multiple retakes for the same scene. The in-studio audience would laugh at the jokes in probably the first one or two takes, post which they would get bored. So by the time the final take was shot, no one would be laughing.
This meant that the laughter was sparse and the audio recorded from earlier versions of the audience laughing couldn’t be synced well enough with the actors' to sound clean. Hence, sitcom producers started using pre-recorded and inauthentic laugh tracks to solve this problem.
In the meantime — and this is totally my guess — they must have also realised that laughter tracks work based on social proof, in that when you’re in a group and others with you start laughing, your natural instinctive response is to laugh together with them. Notice your mouth immediately break out into at least a smile if not a laugh, the next time you see your friends laughing at a joke you’re unaware of.
The producers realised that laugh tracks cut the writers some slack from making every joke genuinely funny. With these, the writers could now get by writing a lot of jokes that weren’t funny at all. Because think about what happens when a joke doesn’t land well and there is no laughing track to fill in the silence.
In this way, laugh tracks became the writers’ crutch and allowed them to get away with mediocre jokes.
The same happens with participation certificates, consolation prizes, and writing Twitter threads with paraphrased content from Wikipedia. You get empty validation for something you did not deserve.
Why is this bad? Nothing wrong with getting some social validation, you might say.
Well, it’s bad if you’re looking to improve. Empty validation, vacuous positive feedback and cheerleading without substance reduce the validity of all feedback. You get hooked to cheap dopamine hits and are deluded into thinking that you’re progressing.
While in reality, you’re simply using your cheerleaders who don't know any better as your laugh track, so that you get permission to perform badly and still get cushioned from the awkward silences of your jokes not landing with those you would actually want them to land:
The ones who can really unlock good opportunities for you; the ones who can jolt you out of your delusions and help you progress in meaningful ways.
Reality is devoid of a laugh track. So make sure your jokes land, or when you need some real help, all you will get is awkward, painful silences.