Harley would need to provide tangible evidence of that being true in order to void any warranties for using those or any other non-HD products.
I'm still waiting for any OEM in the world to provide such evidence for similar claims I've heard over the years.
In other words; no, that is not a thing I've ever heard of being true. Maybe I'll be proven wrong by HD's research group, but I haven't seen anything of the sort before.