A lot of wishful thinking I guess. I don't know how big the Senegalese market from and to BRU is, but with an average GDP per capita of roughly 1500 EUR in Senegal, traffic must mainly come from the Senegalese diaspora in Brussels/Europe. US passengers would still prefer to do a UA/SN combination between the US and Senegal.
There is huge West African community in US East Cost, mainly from Cape Verde (53 000 in Massachusetts), Nigeria, Ghana, Liberia. That's why most US Africa air services are operated from East Coast. Air Senegal could have a commercial partnership with US carrier, if they want to better feed their IAD-DKR. Competition is stiff, but If Air Senegal has a good feeback, peope will fly with Air Senegal
They also eye London, Geneva and some French Cities, such as Marseille or Toulouse.
This winter, they will change their timetables at Paris, to enable connecting at Dakar to their West African destinations. They have an interline agreements with AF, so they use Terminal 2E (Air France long haul flights and non Schengen flights) at Paris CDG.
So i guess if they serve BRU, they will also attract connecting pax, not only point to point pax.
80% of intercontinental traffic linking Africa to other continents is carried by foreign companies. If African states change their mind to improve African Aviation and African airlines are better managed, Africans Airlines could reduce the gap :
https://www.theafricareport.com/16559/a ... le-routes/