The OP put his clothes into a clean and dry bin bag, and then put them in the bin.
Whether he saw her do that, or she told him she had done it shouldn't matter. I am sure that she would not have let the refuse people take it away!
She had told him numerous times that she couldn't live like that, so that is what she was going to do. She eventually went through with that promise.
I am sure that they already have at least one basket or whatever for their dirty clothes, and I assume that they have wardrobes and drawers (or hanging rails and shelves, for their clean clothes), so in this case (with no-one being disabled) it was down to sheer laziness that made her partner behave so slovenly.
Our society (and I expect most other societies around the world are the same) live and thrive survive by having social mores that we grow up learning and adhering to. For those, and I expect there will always be some, who do not want to be stifled/sufficated/suppressed by their societies social mores, but don't want to break any of their society's actual laws, then maybe they need to leave the society they were probably born into, and belong to, and hopefully find other people who think and feel similarly to them, and create a new society that they feel comfortable with.
I wonder how many people would enjoy living in a society where things are always dropped on the floor or wherever, whenever one of it's members has finished with it - whether temporarily or all together? From some of the previous replys to the OP here, it certainly sounds like some Mumsnetters would like to live in that 'alternative' community, which is fine, but I expect that most of us prefer at least some modicum of tidiness (and cleanliness if that is appropriate in any given situation).
I am a married female, and if I behaved like her husband, and he behaved like the OP did, then I would be a bit angry and actually quite a lot secretly amused and impressed. But I do realise that my reaction to certain things might not generally be the norm. I am sure that the vast majority of us Mumsnetters, and probably us humans, are very complex beings, which may very well go at least someway to explaining all the disagreements, sarcasm, put downs, etc that seem to be rife on Mumsnet.
But it may also explain how generous with their time, how lovely and supporting with their words, and simply how helpful and understanding some Mumsnetters are. I suspect that some of our wonderful Mumsnetters can come from either/both camps depending on both the subject matter, and whatever is happening in that particular Mumsnetter's life at the time. I also expect that it might take a lot to change any of the few trolls that we sadly come across, from being a troll. If we knew their life story we might actually feel sorry for them.
Anyway, if an otherwise happy marriage or partnership reaches a stalemate over something that is very frustrating/upsetting to one of them, and just happens due to sheer laziness on the side of the other one, then a well warned, non aggressive act on the upset partners side - remember the OP did not damage the clothes in any way. I am sure there was no chance of them being taken away unless her partner couldn't even be bothered to retrieve them from the bin - and one that was not abusive in any dictionary defined way that I know of, may have possibly been the best way in their relationship to reach a mutually beneficial understanding.
It wouldn't matter to me whether it was a man or a woman who had used this technique to try to get the other partner to know how frustrated and upset they were.
@Timeforchange13 obviously knows her partner well, and her actions worked at least this time, he apologised to her, and actually washed and hung up the said clothes. Whether her actions will have a long term affect is still to be discovered.
However, one sentence of the OP's does dismay me a little, and it is possible that the OP did not actually mean it like that, and just used a poor choice of words (something that I am frequently guilty of, and could kick myself about when and if I realise later what I said) is:
"Sometimes you just have to put them in their place"
That sentence made me cringe. Imo not only should it never - or at least hardly ever - be said (who are any of us to put another person in their place - whatever that actually means) - but in my eyes it made the OP sound very smug, and smugness is one of my big dislikes, along with arrogance. I think that they probably go hand in hand together, and I don't know why I have such a visceral dislike to both characteristics, but I do, which of course is my problem, and probably shouldn't be (and isn't?) of any concern to Timeforchange.
I expect I will get the usual eye rolls, FFSs, or even a biscuit, for this once again far too long indulgence in writing down my own thoughts, but then I think that many Mumsnetters take one look at my username, and/or the length of my musings and give my comments a miss anyway. I can't say I blame them if they do! I sometimes wish that I could climb out of my head and have a rest 🙄🤭