I can't tell if I'm being unrealistic here or not.
Have BG DTs, 3.5yo. Both super chatty when they want to be, but at home they don't always listen, so don' always answer if I ask them a question.
DS has possible hearing issues and mild speech delay, but it's all being monitored/assessed, and he's quite capable of a super detailed conversation about steam engine pistons, so he can chat fluently and listen to detailed info when he wants to (he just struggles with clarity of pronunciation sometimes).
But when we are with other adults they clam up massively, often don't answer simple questions, and lose their manners unless I RAM it home ("What do you say? Thank You!"). Even 'Would you like an ice-cream?" didn't get an answer to one of my mum friends yesterday.
Today on our way back to pre-school after a long break I chatted to them in the car about how they should say a nice big GOOD MORNING to their lovely teachers who they hadn't seen for so long. I hid and watched while they ran into the playground where all the other kids and teachers were, saw the - lovely and super approachable - teacher call over to them to say hello, saw DD shoot her a bit of a funny look, neither of them say anything in return, and both run off to play.
It feels SO rude, and I hate rudeness, but I don't know if I'm expecting too much. I'm on the shy side, but I don't think I go round ignoring people or blanking them!