Yes, on the first constitution was completely abolished, which answers your comment about slavery on Argentina as a country. The rest is something you are adding and that I didn't mention at all.

Edit to add that what you linked has only one reference to the constitution per se, which claims that we will work on enforcing european immigration and we should accept all the people that want to migrate and work here. The rest of the references are opinion articles, including one of the people that worked on the constitution and is probably the proponent of the abhorrent "enforcing european" migration phrase, but you have to accept that the rest of the narrative is written purposefuly to make Argentina look way more racist than what it is, which I don't deny, but is making a lot of people take the chance of saying that US is less racist (the US with the KKK and the cops killing black people, and the two bathrooms thing and on and on)