Pre-Merino, wool was quite itchy. I wonder if you are thinking of "old" wool. Modern merino is some very soft stuff.
> Merino wool is able to ditch the itch thanks to its fiber's smaller diameter, or being “finer”. These fibers are more flexible and softly bend when pressed against the skin and, therefore, don't itch like other wool.
https://www.smartwool.com/discover/why-merino-wool/merino-wo...