Sure there is. All the way back to aspirin. Before aspirin, there was salicylic acid, which has some painkiller effect but tastes awful and causes stomach upset. Researchers at Bayer found that tacking on an acetyl group produced acetylsalicylic acid, with the same painkiller effect but fewer side effects. That's aspirin.
Drug companies are trying to improve on Ozelympic.[1] The big win will be when somebody comes up with a pill form rather than an injectable.
I see your point. But consider that drug generations are generally not defined by the manufacturer, but by the broad community of researchers and clinicians finding step-changes in their effectiveness/side-effect tradeoffs.
So by definition, if they ever consider a "new generation" of GLP1-agonists, they will be better by definition.
Drugs are not like a smartphone. There is no reason to believe you can improve on them (except on price)