If I'm stuck in the right lane and there's someone on the onramp trying to merge, I'll always let them in, either by slowing down or by changing lanes if there's a space for me. Always. I'll never cut someone off if they're trying to merge.
I've learned how to merge so I don't need people to "let" me in......provided there is the space I gauge my spped so I fit in the space.....although sometimes people speed up to cut me off but I get over anyway -- that's why there's more than one lane...
I was always taught that when approaching an on ramp you should get over into the left lane to allow people to enter the highway....