How could it be?
Because more than anything, Star Trek is a business and Paramount likes making money, so regardless of how lame it was to keep bringing Worf back, if Nemesis had been successful, they would have found a way to bring the TNG crew back one more time, simply to make more money...even if it didn't make sense and was a terrible movie as Nemesis proved.
And creatively, it actually wouldn't have been too difficult to come up with a story that brings the crew back together and teams up the Enterprise and the Titan...TUC featured both the Enterprise and the Excelsior though the circumstances are vastly different and the Excelsior had substantially less screen time, the precedent for a two ship film was set right there....or even before then if you want to go all the way back to Wrath of Khan with the Enterprise and the Reliant.
And that's considering that Paramount would even bother to stop and take into account the creative aspect of making another movie. If Nemesis had been successful, they likely would have taken whatever elements of TNG were left and pushed forward to get another movie out.
Paramount's drive to make money on Trek by any means necessary, no matter the quality of the product they were selling, is what ultimately killed the franchise. And in the end, fan fatigue was partially correct. We were tired of Trek. We were tired of bad
Trek and we stopped watching.