Argentina allows dual-citizenships. Source: https://en.wikipedia.org/wiki/Argentine_nationality_law#:~:text=Dual citizenship is accepted by,nationalities that has an agreement.
In 2009 Argentina decided that the Argentine Citizenship is a human right and cannot be renounced.
Note that, per this article, "Unlike most other countries, Argentine citizenship cannot be renounced and can only be revoked if it was obtained through criminal means, such as fraudulent documentation.
Consequently an Argentine citizen may not be able to acquire the citizenship of a country that requires renunciation of other citizenships; however, many countries waive this requirement if renouncing the other citizenship is impossible."
I'm an Argie with dual-citizenship. All of my ARG family members are dual citizens.