I do think the OPs lie about knocking on the wrong door is stupid and unnecessary, and also finding the idea you can tell anything about neighbors in 10 seconds beyond most basic assumptions such as if they sounded impatient, rude, have kids, a loud dog, a tidy home etc from the interaction is a little ridiculous.
I think that there is value in openly and honestly knocking on neighbors doors when considering purchasing a property to make enquiries.
This idea that a person's peace and quiet in their home is being shattered by someone asking a few questions and is somehow rude comes off as rather dramatic and hyperbolic (the very delicate flowers on here sound like the kind of neighbors you might need to avoid cause you coughed too loudly and they complained you were a noisy neighbours shattering their peace) Oh woe is me, I had to answer two or three questions from a stranger...the horror. The inconvenience! 🙄
Answering a few honest questions about the area or house is rude these days? Too much of a burden on your time? Considering a House is the single largest purchase and investment of time and money that most people would ever make in their lives, I think the due diligence of inconveniencing someone for a two minute conversation is more than reasonable. It is essential. No reasoanble person would begrudge answering a few questions if asked politely and openly.
Sure, let's just drop six figures on a property that we only have superficial knowledge about when a brief conversation with a neighbor could give you first hand knowledge and warn you off potentially huge problems such as flooding, structural issues, antisocial behaviour, parking issues, problematic neighbours, noise issues etc etc.