class could also be for disambiguation.
example from cppreference:
int main()
{
Bar Bar(1);
class Bar Bar2(2); // elaborated type
}
Since the first variable is called Bar, the second time you write Bar to declare a Bar you need the keyword class to disambiguate and specify this is a type, otherwise you get an error because the expression “variable_name undeclared_var_name(2)” have no meaning.