'Respect' means many things, not one or two or three. It is an infinitely flexible word.

You can be told to respect your elders, to respect women, to take your hat off to be respectful, to respect someone's boundaries, to respect a weapon, to be respectful by listening quietly, to respect nature, to pay respects the dead, to respect yourself, to respect the law, to respect the game by following the rules. You can earn respect, give respect, or demand respect.

These all mean different things, but it is one thing: the correct regard for something, either being shown or deserved. 'Respect' can be used, over time, to convey an entire world view and code of conduct. How much respect someone or something deserves, and how that is meant to be expressed, can cover almost anything about anyone's behavior. People differ in what they think deserves respect, or how much of it. I cannot precisely say what 'respect' actually is any more than I can say what 'polite' is. Statements about respect or politeness are arguments about the right way to act, not facts about the world.

If this is alien to you, you can just think of it as 'polite' but with a lot more weight to it.

How familiar this is depends a lot on your background. I've heard the word used this way thousands of times. It is so distinct and specific that it is effectively a matter of speaking a different dialect. For many people, it seems that the only time they hear 'respect' used in this way is from an authority figure who is telling them what to do. Conversely, if this is in your background, language about what to do or how to behave that doesn't use this device is fundamentally alien. Saying something is "offensive" and that it's "disrespectful" are often more or less interchangeable, and which one you hear depends primarily on the dialect of the person speaking to you. In either case, you're likely being told what to do by someone who speaks a different dialect than you do, and this changes how it lands.