Yes, but some proponents of the concept, seem to pick and choose what is and what is not a sin.
The Biblical definition of sin is transgression of the law. Breaking what God says is the law.
"Whosoever committeth sin transgresseth also the law: for sin is the transgression of the law. - 1 John 3:4
Wearing mixed fibres is forbidden, in the Bible,
I knew that.
as is breeding different types of cattle
Didn't know that one, and I'm a Sabbath guy..
as is eating meat on the sabbath
I don't think so. It sounds like a Catholic thing, like fish on Fridays or pancake Tuesday.
nd many other things..which are ignored.
There was a bunch of things the Jews made up back in the day that were not in the Bible. Like how far you can walk on the Sabbath. A Sabbath Days journey.
Yet other things, like men lying down with men, are hot topics and loudly proclaimed as an affront to their God thing. Why is that?
That one's a biggie. There's little sins, like don't get tattoos, or pierce your body, and there's bigger ones like men lying down with men. In Leviticus that one is a handful of things God calls an Abomination.
"You shall not lie with a male as with a woman. It is an abomination. - Leviticus 18:22
And then He goes on to warn about mating with animals and so defiling ourselves. And none of our women should have sex with animals. Then He says that by doing any of these things we would defile the land and then the land would vomit out it's inhabitants.
Then He talks about having to come and visit the land after it becomes defiled. And it's apparently not going to be a nice visit.
"For the land is defiled; therefore I visit the punishment of its iniquity upon it, and the land vomits out its inhabitants.
It's always the same thing. Days of Noah, therefore I visit the punishment of its iniquity upon it. Days of Lot, therefore I visit the punishment of its iniquity upon it.
Days of Lot again, therefore I visit the punishment of its iniquity upon it.
Wash, rinse and repeat.