nah "Somalian" is a stretch if u already know for certain that we are referred to as Somali it js sounds out of place or strange to be called SomalianTo me somalian aint that bad, I would say the real offensive term that ajnabis use is "zoo mali" because it implies that we belong in the zoo.
think of it this way with the country of Mongolia which sounds/ends the same as Somalia but has an opposite way of referring to the people
you wouldn't call someone from Mongolia a Mongoli but you would say they're Mongolian
whereas you would call someone from Somalia a Somali but you wouldn't say they're Somalian
But in reality its going to certainly happen that someone says Somalian and its not really that crazy/ something to tweak about because more often than not randoms and most people really wouldn't know or care that much to know about the difference in pronunciation between Somalian and Somali ;lets all not go that far to making it a bigger thing than this kind of thing is.