Abdullahi Yusuf was a militia leader, he started a dowlad. SNM were militia and they started a dowlad.
The failure of USC changed the study of International Relations. Today, when major powers discuss regime change, they always consult the fall of Barre as the prime example as what not to do.
Before 1991, the US would usually fund a militia group to overthrow a government, sometimes violently, without it descending to anarchy. Somalia was the first time a modern nation state descended into pure anarchy, because of said militia group.
Somalis can choose to admire Aideed, but his name is tarnished in the history books.
Neither of the examples you listed are comparable to Caydiid and the USC.
The SSDF made peace with Afweyne in the 70's and didn't take part in the heavy war against Afweyne. Furthermore they too were fighting in the years after Afweyne's removal and Puntland wasn't created until years after Caydiid's death.
The SNM were very different because they were essentially led by a committee of elders and therefore it was much easier to organise the peace conferences that led to the formation of Somaliland. They already had a peacemaking mechanism built into their structure.
In the years following Afweyne's demise, none of the Southern militia's involved in the war were truly interested in making peace, including the USC, SPM, SNF, SDM etc. They were all hellbent on gaining power, destroying their enemy and getting revenge. How was Caydiid or any one of the leaders of those militia's expected to get all the others to agree to form a government?