With species like squirrels that are more remotely related to us, there is more scope for an argument of parallel evolution, sure. Maybe their similar behaviour developed independently and has a different cause especially when other mammals do not exhibit this behaviour.

With our much closer relatives such as apes though that exhibit so many more behaviours that are very close to ours it’s much less plausible. If all of them exhibit a common pattern of social behaviour with ourselves, arguing all of them could have independently developed this behaviour separately from us and each other, to appear indistinguishable, that seems highly implausible.

Even with squirrels though, as mammals they exhibit many behaviours common to all mammals. Behaviours we exhibit as well. So if all mammals have these behaviours and we do too, if our behaviour has a different cause, at some point our ancestors must have switched from exhibiting the behaviour due to the common mamalian cause to exhibiting it due to this new cause unique to us. I don’t find that account very plausible either.

Did our ancestors stop exhibiting this behaviour first, then develop new neurological mechanisms that happened to replace the lost behaviours? When did that happen, before or after we diverged from other apes? Maybe they have these behaviour for the same reason as us but other mammals don’t? Did we develop a parallel mechanism and the behaviour transitioned to the new causal mechanism? I’d expect to see some residual evidence in our neurology or behavioural patterns of that having happened.