The extant government in Rwanda was overthrown by a force led by Paul Kagame, made up of Tutsi exiles in Uganda. He is also now widely believed to be the man who ordered President Habyarimana's plane shot down, killing Habyarimana and Burundi president Cyprien Ntaryamira. That killing and the invasion destabilised the country, and led to massive killings of Tutsis by Hutus. In the country liberated by Kagame's forces, there was also extensive slaughter of Hutus. To this day, Rwanda under Kagame is an ethnic dictatorship, in which the majority group, Hutus are excluded from all political power, and thousands are in jail.
The argument that France is the villain rests on the view that they ought to have helped Kagame overthrow Habyarimana, and that they either stood back or assisted in the genocide. But there would have been no mass killings if Kagame's RPF had not invaded. The argument that France did not play its part is not an anti-imperialist argument, it is a pro-imperialist argument, a demand that France ought to have set the course of Rwandan history in another direction.