Is politeness outdated?

Perhaps I was just raised with some old-fashioned ideas, but it seems to me that most people aren't as polite as they should be. It's an uncommon thing for me to hear people say, "Excuse me" when they squeeze through a crowd, or hold a door open for the person behind them. I even had a woman act insulted that I'd held the door open for her once.I find this to be more than a little disturbing, since I was raised with the idea that all people deserve to be treated with a certain base level of respect, unless they directly proved themselves unworthy of that respect. In my view, being polite is the method of conveying said base level of respect. However, most people seem to prefer to ignore other people, as opposed to at least giving them a friendly nod or otherwise acknowledging that they exist.

So, I wonder, where did we go wrong? What happened to cause this change? Why don't people care?

Frankly, I can't come up with an answer other than that people just seem to have slowly given up on the idea, or maybe forgotten it. And, really, it's not something that should be forgotten, being generally nice to the people around you.

So, next time you open a door, check if there's someone behind you to hold it open for, or if you pass someone in the halls give them a friendly nod. The more people connect with each other, the better off we will be.