The reason why the entirety of greater Somalia is in the situation it's in today is it's emotional people. From Mohamed Abdullah hassan who refused to be the undisputed king of Somaliland when he was defeated to Mohamed siad barre who refused the Russian offer to take the entirety of Ogaden but without dire dawa, Somalis have always wasted great opportunities wither it was for the great good or for their personal benefit due to their arrogance. You would think that years of civil war and chaos would teach the Somali people to be a little more pragmatic but they somehow became even more emotional than previous generations. But guess who learned to be pragmatic? The likes of HSM. Somalilanders will endup in a best case scenario like the kurds in Iraq, Turkey or Syria or in a worst case scenario like south yemen during Ali Salah's era.Yes, Somaliland has been defacto independent since 1991 but that is just it, defacto. Its bilateral declaration of independence has not and will not ever be recognized by any state because Somaliland is considered de jure apart of Somalia by the international community. For example, Georgia, the country in the Caucasus has its own break away states in Abkhazia and South Ossetia which is hasn't controlled since the 90s. The international community considers those territory to be rightfully apart of Georgia so being independent means nothing when everyone still considers you to be apart of Somalia.
If push comes to shove and if HSM has the balls to do it, Somalia can squeeze Somaliland dry and put heavy economic and political pressure on it. Don't confuse the fact that Mogadishu has no direct control to meaning FGS has absolutely no sway in Somaliland because at the end of the day, an Abgaal nigga in Mogadishu signs the papers to allow foreigners to work with Somaliland.
Somalia will not fall for such transparent black mail attempts. Its clear that the Las Anod war has proven so disasterous that Bixi is willing to resort to such measure despite the unpopularity of the deal back home.
Nothing is terrible about the deal. Turkey is willing to built up Somalia's navy and built maritime infastructure to drilla and survey oil all without Somalia paying anything up front. They only want a 30% cut of the revenue generated which is nothing. And contrary to what you believe, the deal has been talked about since 2020 so it was not a reaction to the Ethiopia-SL deal, it was always in the works. Meanwhile Somaliland in exchange for Ethiopia annexing their lands will be getting a 20% cut of an airlines that only makes a billion a year in revenue. Its by an far away the worst deal than what Somalia has.