Dreadlocks as a term has become a convenient moniker for them regardless of what you end up terming them. Everyone knows them as dreadlocks, and when you can't be arsed to have a long in depth conversation about the cultural context, or when it's not even necessary, then that's what they are.
My context comes as a result of the alternative counter culture of the 90s in Britain, and growing up in North East England, you just never saw many black people full stop, never mind with dreads. There were a couple of Sikhs at my school, and it was the Indian and Pakistani communities that were most common. The first people I encountered with dreads were almost universally of the scruffy hippie, alternative, traveller culture types, mostly hitchhiking around New Model Army and Levellers gigs. So dreadlocks for me have always been wrapped up with in that scene. The one Rasta I did meet back then was white, and it was years before I encountered a black Rasta.
It's always good to educate yourself about a subject, but I have found the most vitriolic commentary about the subject seems to come from Americans who only see their own America-centric world view, totally discounting the Native Americans documented wearing locks.
It's hair. Hair knots when you don't brush it. It's that simple.