During rush hour, on my i-65 stretch, if I am in the right lane, I always give room for people to merge in front of me. If I’m in the passing lane, I keep the spacing minimal. I don’t let people in if I can help it.
I feel so strongly about the latter that if people are finding their way in front of me, I’ll get out of that lane because I’m not paying enough attention to my speed.
“I don’t let people in if I can help it.”
You say that as though you think it’s okay.
The problem with what you describe (even putting aside any discussion of propreity) is that you’re putting yourself in danger if you’re doing 60 or more mph and you’re leaving such a small space between you and the car in front of you - this is how multi-car accidents occur when the lead car hits a deer or has some other reason to stop suddenly.