It really depends on the kid and the complexity of the message. Young kids are still learning the intricacies of the language and building a vocabulary. Not talking down to them helps build those skills up. But at the end of the day, if the message is not getting across, it’s the fault of the communicator.
Plus it’s an annoying flex to say “see how amazing my kid is? It’s all because of me!” Some kids just pick up language easier, some kids sleep all the way through the night earlier, some kids toilet train easier, etc. Usually it’s better for parents to quietly take the little victory rather than treat it as a reflection of their amazing parenting skills.
Ah yes, nature’s ghillie suit.