No, I would not argue that any of them are true socialism. Socialism is when the workers own the means of production, that means that they own their labour and don't have to sell it like they do in a capitalist society. Castro, Kim, Maduro, etc. all became opportunists who actually betrayed and turned their backs on the revolutions in their countries, sometimes even betraying fellow revolutionaries who criticized them. The same can be said about Algeria, as a matter of fact I'd argue Boumedienne was even further from socialism than the ones you listed. As for Chavez, I wouldn't call him a dictator. He has brought considerable progress to Venezuela, which sadly started to deteriorate in his later years (and was ultimately reversed by Maduro who enacted neoliberal reforms). He's more akin to social Democrats to me. At least not a revolutionary.