If you get overcome by the cuteness, you might not be able to properly take care of it, so the brain needs to bring us back a bit. This is apparently where cute aggression comes in, according to evolutionary theorists.
Source: Nice News, March 4, 2024. Link.
. . . for people who tend to experience the feeling of ‘not being able to take how cute something is,’ cute aggression happens . . .” – Katherine Meltzoff, PhD