Growing up I was always told that cotton would shrink in the dryer but polyester wouldn't, and I should just check the tag on a shirt to find out if it would shrink (which usually would say something like 100% cotton, 100% polyester, 50% cotton/50% polyester, etc.). Seeing the title on this article made me think that it would be a refutation of that conventional wisdom, but it sounds like what I was taught growing up was basically correct.
I can't help but be curious now; is this something that other people my age (born in the early 90s) had heard when they were kids? Did people who grew up earlier than that hear it when they were kids, or did this idea maybe not reach mainstream status until a bit later (maybe my parents were relatively early in repeating this wisdom)? Or maybe it's something that used to be common knowledge that's been "lost" to newer generations for some reason? I'm genuinely a bit surprised to see that this article was published just last summer, since I assumed that the basic premise would be have something the average person would have learned before then from existing sources. Maybe I'm assuming too much about whether this article was intended to be about the "what" rather than the "why", but the language seems intended to be approachable to those from a non-scientific background (e.g. "on a chemical level, there are also links between the chains called hydrogen bonds"; I would expect someone talking to another scientist to be more direct and say something like "there are hydrogen bonds" with the expectation that they understood what they were already).