I also agree with you OP, and with rocks' very clear post.
I don't necessarily agree with you in all the details - I don't like time out, never use it, and toys on the table? - meh. But yes to boundaries, from a very early age - it doesn't mean being cruel, and it doesn't mean you think your child is always going to behave - it means making clear to them as soon as they can understand, what is and is not OK, with clear consequences, and consistency. Doing this is not just a good idea because it helps your child to behave - IMO it is what small children really crave. They want to know where they stand, it makes them feel secure and happy - I think a lot of kicking off happens when children are fliundering around without boundaries and trying to get someone, anyone, to make a stand.
Yes, children are different and I accept that I have a moderately well-behaved 3yo myself, on average, and if I have another I might find out how different they can be. But isn't it possible that if you only ever do this kind of namby pamby "don't do that dear" and never take action, you might well encourage a child to think it's OK to behave like this, and their behaviour might have something to do with that? Surely no one on here is seriously suggesting that children's behaviour at age 3 has absolutely zero to do with how we bring them up? And if you do think that, as other posters have said, when it that magic tipping point when we suddenly start having an influence?
If you cannot defend the idea of basic boundaries and discipline for fear of being called smug, then I despair. The OP just wants her friend to step in - not to create a perfect, docile child, just to act like a parent.
My DS can kick off with the best of them. But I make it clear when he's out of order, I use consequences and I follow through with them, even if it means going home if he won't behave (though that's rare). Yes I'm embarrassed sometimes, but not half as embarrassed as I would be if I couldn't even bring myself to tell him no.
OP, I have friends like this too, people I have never, ever known to take a firm stand with their DCs (and btw I am not talking about smacking or shouting, just firm boundaries and consequences) and I see their DCs growing up fairly clueless about how to behave. I think that's a parental cruelty, tbh. People think it's important that their kids learn to read, road safety, etc. How to behave around other people is also an essential life skill.