*was there a long campaign or something to get the size changed to extra large?
Did I miss the marches? The protests outside Kleenex's head offices?
Or were there a few tweets and someone in marketing said 'oh let's change the name of the size, tissues are just tissues.'*
This.
This wasn't a massive campaign. Someobe noticed and changed it. So what? Sure its not the most pressing issue in the world, but it matters a little. Gendering tissues is unnecessary.
It's also the many, tiny actions of many individuals that will help drive change. I wouldn't be happy with 'lady-tissues' either. If a woman challenges a small cat call, are we calling that 'pathetic'? Or is it recognising that letting little things slide contributes to bigger problems?