I also think some people with high iq learn to fake a lower iq and thus, go below the radar.

How could you tell the IQ of people you were working with? I'm struggling to see how you could arrive at this conclusion unless you've 1) worked with an inordinate number of both high IQ individuals, who 2) explicitly mentioned their IQ scores to you.

Personal hypotheses such as this one spread like wildfire online because they're easy to state, play to a narrative and are extremely difficult to disprove. They're stated confidently while skipping over so many little gaps - for example, I don't see anything obvious about how high IQ individuals would stop trying to explain things to low IQ individuals. It makes sense as a heuristic for explaining the behavior of one particular individual who is perhaps a misanthrope or has little patience. But it's very poorly generalizable.

How high an IQ are you talking here? I have a moderately high IQ (~130) and being able to explain complex topics to family and friends in a simple enough way that they understand it is one of the things I enjoy most, probably because having a basic summary then the meaty material is how I best learn complex topics.

I don't think humility, empathy, and high IQ are mutually exclusive, though given some of my experiences with smart people I can see why you might think that way.

I am not sure about that - those people I know who are waaay cleverer than me have bad days of course, but mostly if you ask them to explain the subject they love, they will talk (down) for days without getting bored.

Perhaps it's true for us all, we love to talk about what we do.