As someone that’s an introvert and has social anxiety I’m usually caught off guard when people do speak to me. All I can manage is a smile and a nod or a very quiet hi. I just want to get to where I’m going and back home with the least interaction as possible. That’s as polite as I can be. I will say though that if someone says something to my lo(little one) I always have them say someone back. But my lo is also an extrovert and craves human interaction.

I didn’t vote on the poll because I’m not sure that your version of politeness fits me.

Perhaps you should add another option: "I am polite when warranted"
I am vegetating in caravan park, small community, I started greeting when I came with about about 2 metres (metre is a civilised measurement equivalent to about 3 feet plus sales tax) but when there was no reply after several attempts I stopped. I find it extremely weird especially in an enclosed space when someone passes at less than 05 of a metre (metre is a civilised measurement equivalent to about 3 feet plus sales tax) and the persons walks past without acknowledging my presents.

Unless they act like idiots then I can be quite abrupt

Property laws go a lot farther than politeness.

I don't think not saying thank you or whatever when you are getting on or off the bus is too big a deal. You're taking them to where they don't want to go and possibly where they get bullied every day. Also, they could just be in a bad mood, so I don't think its too big of an issue. I always say please and thank you and greet whoever serves me, but if someone doesn't respond or whatever I just assume they're in a bad mood and don't really feel like talking. Which I totally get.

I agree with you 100%.

It’s not so much that I’m not polite, it’s just that I’m blunt and up front. Which people mistake for rudeness. But, if I like you and have known you for a while, I’m more likely to sugarcoat things a bit more.

The first time I heard passengers thank a bus driver was in Australia. Now I do it and my younger daughter, now 28, always says it with a smile, even when she is not necessarily in a good mood. It a bit of a social lubricant.
One day we took the suburban train together and after exiting I started running towards the head of the train. "Daddy, where are you heading?" "I just want to say Thank you to the train driver."
Do you realise that these guys never get a word of thanks?

Before settling in Australia I lived in a could of other countries. After over 30 years in this vast open air slammer I still think Australia, perhaps just Queenland, is generally very rude. Even the politeness and courtesy is just a very thin cheap veneer. I worked as a teacher here and realised how there is no fertile ground for these qualities to take root. I often blame it on the rough sports and the macho attitude that is catered for in all the beer ads, though I really like some of them.
For many years I had the habit of turning off the engine of my car when I knew I had to spend more than a few seconds at a traffic light especially near restaurants. One day I was sitting at a red light on a popular dining strip. I knew the sequence I that I had to sit there for 90 seconds. I turned off the engine and dimmed the lights. Some guy walking past said: "Mate, your lights are off." "Thank you. I know. I turned off the engine.." His reply: "What a fucking wanker." This not really such an exceptional reaction. I wonder whether this person is now calling all the drivers of cars whose engine turn off automatically fucking wankers.
Schools do nothing to promote the old fashioned virtues. I found it an uphill struggle to convey some other ideas to my daughters. They turned out to very polite which unfortunately is often perceived as a weakness by bullies.

I find it strange when I greet people politely and they respond negatively - I wonder what they heard about me - there are a few people in my housing scheme that I have given up talking to because they are pretty ignorant and it doesn't cost me a thought - 26 people are a lot to try to get on with and if they don't like me I don't want to be around them either.

I try to avoid people. It lessens the chances of me being impolite.

My real exception is when someone is unkind or rude to me or someone else. I don't hesitate to say something like, "Civliity is not your strong suit, is it?"