Wiktionary[1] says that the expression has existed at least since the 18th century, adding this interesting note:
> À noter aussi que durant ce siècle, la notion de « lumière » était une représentation métaphorique de la « connaissance » (cf. : siècle des lumières). Cette expression peut donc aussi se traduire de la façon suivante : « à la connaissance d’aujourd’hui » ou « au savoir d’aujourd’hui ».
Roughly translated it says that light could be used metaphorically to imply knowledge, so "au jour d'aujourd'hui" could be parsed like "to the light of today" and from there "to the knowledge of today". Now whether that's a justification after the fact or the real origin of the expression, who knows...
[1] https://fr.wiktionary.org/wiki/au_jour_d%E2%80%99aujourd%E2%...
The same thing happens in Spanish ("subir arriba" and "bajar abajo"). It became a serious pet peeve after someone pointed it out to me, until I noticed that people only make this "mistake" in either very noisy places or very time-sensitive situations. It's more a desired redundancy (even if not conscious) than the accidental redundancy in the case of au jour d'aujourd'hui.
Writing about this reminded me of how some people will try and make conlangs that compress as much information into as few sounds as possible, only to render them unusable - whereas within a rounding error all natural languages have the exact same information density and Signal To Noise ratio.
Edits: grammar, formatting.
"I climb up" might give a somewhat better impression of how "je monte en haut" sounds in French, although I suppose that you can very much "climb down" in English so it's not a perfect match.
Pet peeve of mine, there also was the word "sociétal" used instead of "social". Which led me to use the locution "les réseaux sociétaux" because fuck.
Society is opposed to private, fragmented circles ("some" audio engineers, "some" people), subset communities contained in society. Externally, society as opposed to other societies i.e. countries or cultures.
Then one day some r/Iamverysmart self-proclaimed intellectual heard "societal" and liked the word, emotionally, and began using it — that's how you learn words, right? By using them. Trial and error.
So, so many errors.
But others liked it too. And ever more. Lovely errors. And suddenly because people confused it with "social", it began an "umbrella concept" for "everything involving many people doing stuff together". Sure, that works for society and social matters. It's also as empty a concept as you can make. But in the Twitter age, it's OK to use 1 word to mean 20 things and never detailing any of it,
because fuck.
Agreed.
The truth is so few people care, it's not even worth the time to delete -et-. Those who do care, speak with others who understand, and ignore the rest. Sad state of affairs, but I've grown convinced it's just human nature, and has been virtually forever.
[1] https://www.persee.fr/doc/rfsoc_0035-2969_1991_num_32_4_4079
Hence why we say sécurité sociale et non sécurité sociétale.
jusqu'a maintenant = to this day
au jour d'aujourd'hui is just too awkward to use, it even sounds bad.
I wouldn't say that, it's still debated whether it's correct or not.
This is typically known, even among french people, to be extremely bad french, so it is pretty much only used by ignorant journalists.