I would reduce that to 10-15.
If you're not doing sick neonates, cardiac w CPB, and enough of those (albeit rare) 'index' cases several times each week, I don't think you're being properly trained as a pediatric anesthesiologist.
And even if, like myself, you decide not to end up working at a tertiary Children's Hospital with those kinds of patients or sick kids in general, you still need that background to help you care for the healthier ones.
Program expansion has become way too diluted, with many programs basically a continuation of residency as an extra year of tonsils, hernias, and circs. And even if that's your career plan, you need to know the rest of the pediatric anesthesia field.
I had no interest in OB during residency, and don't do any now, but we'd never consider an anesthesia program valid if it didn't include those painful months and nights of training.