How should journal editors address accusations of racism?

If the argument is that the preceived 'racism' inherent in the theory actually disproves the theory, then it should be handled like any other academic dispute, without regard to the furore that the mere mention of the term 'racism' produces at the moment. If the argument is about whether or not the theory is itself 'racist' it's not an academic debate at all, but a socio-political one; another forum is probably more suitable for discussing it.

"If the argument is about whether or not the theory is itself 'racist' it's not an academic debate at all, but a socio-political one; another forum is probably more suitable for discussing it." That unfortunately won't work as most fora in the public realm if not explicitly left-wing and heavily 'moderated', thus limiting the range of 'suitable' subjects for discussion, are monitored by the self same left-wing who will accuse, pile on and even report discussions to the Police for 'racism'. Academic freedom has been and continues to be eroded by the left-wing requirement for ideological orthodoxy, ASSisted by University 'managerialism' who fear controversy of debate and bad P.R., along with self-censorship due to the atmosphere of hate directed at those that question the embedded neo-Marxist ideology. Until we have the equivalent to FIRE in the USA any the Academic freedoms we have been able to use to discuss issues others would rather we didn't will remain under threat. https://www.thefire.org/