Though it wouldn't have lasted for long in that format, it was beginning to look old hat in 1992. I doubt the presenters would have lasted much longer either. However it would have been a more gradual change than the introduction of Rainbow Days was
Yes, it had been on air for twenty years when it ended, and a few years earlier Play School, an even more cherished pre-school show which also had a huge legacy, had ended after 24 years, so it probably wouldn't have lasted much longer. Of course, a lot of Thames shows continued after they lost their franchise, but Carlton presumably wanted to launch their own shows as well and there were only a few pre-school slots to go around.