The difference isn't skin-tone, but who the refugees have been. Ukrainian refugees are mostly women, children and elderly, and practically no men ages 20-40 (because they stay behind to fight, and hopefully someday make it safe to return). From Syria, Palestine and Iraq the humongous vast majority has been 20-30 year old males who rather than fight for their lands took the easy way out; they have left their families behind to somehow manage, and themselves went looking for free iPhones in the West.
During the past 36 hours tens of thousands have escaped from Russia, seeking for refugee asylum once they get to the border. Over 90% of them have been men aged 20-35 who didn't want to stay and fight against Putler and his cronies, and who left their families behind. Despite their light skin-tone it is pretty safe to guess whether their treatment in the West will be closer to the Ukrainian refugees or the Syrian refugees.