It's an MoU- a non binding agreement. Any xabasha leader could've made such a deal anytime since the 90s. There's a reason they choose to do it now that for the first time ever since 1992,
a Somali authority is recognised as the sole ruler of our sovereignty and trusted with buying any type of weapon. We have to understand this from their perspective. A united Somalia is a threat. SNM, USC,SSDF all of them were trained, funded and operated from their territory. They reached their goal with the fall of Somalia and had no reason to make strong moves in the country, other than keeping the status quo and the balance of power between the qabiils.
Now there won't be any balance as the FG will have a conventional army that'll be able to safeguard it's territory. Even when the FG chooses not to confront SL there will be SNA planes making reconnaissance flights over that area. In the end it's in our own interest that we don't kill each other being played as pawns IA.