Physics textbooks are notorious for sentences that include one word and an equation. Something like this:
For (almost all) students, the steps that led to that equation are not obvious.
Same with a lot of things people say that are preceded by the word “obviously.”
Here’s the deal: We don’t know what you’re thinking, and your statement or conclusion is not always obvious. In fact, I bet more often than not is it not even fully thought out or logical, or that it’s not even obvious to you.
There are really only two reasons someone would use the word “obviously” so condescendingly, even if unknowingly: 1. Their knowledge is domain specific, and they have no social awareness; or 2. They’re just making things up.