Yes, they should, but the people of Donbas are Ukrainian, and the majority are certainly not separatists. Russia's continued attempts to influence the region still add up to very little in terms of support by most residents, and you can find surveys like this: https://theconversation.com/most-people-in-separatist-held-areas-of-donbas-prefer-reintegration-with-ukraine-new-survey-124849