Um, nope. There are a lot of myths in our world but I'm afraid this isn't one. Not going to debate it here but for every system there are designed operating parameters. This does not mean you can't USE mismatched feed line or antennas it just means there is a cost in doing so. Depending on your set up the difference between RG-6 and RG-8x may be negligible in your specific case but it is there.It's all a myth that you have to supply 50 ohm coax for a 50 ohm antenna.