for example I've read that Akon financed renewable energy plants in Senegal.
That's a great way to help!
Building an entire new residential city founded by a single person in his own name for rich people? not so much IMO.
Well, if you are building one where
The economy of Senegal is driven by mining, construction, tourism, fishing and agriculture, which are the main sources of employment and 75% of the population lives in chronic poverty, maybe there is something more urgent that could be done.
Unless you think that UAE and Dubai are a good example of development.
Plus, foreign aid did not exactly work well in africa; maybe it is better to teach people how to fish this time
USA military intervention is what did not work if you ask me.
Also USA support to Riad regime is not exactly for the good of middle east.
Having said that, Senegal learned to fish a long ago, it's politically stable with a stable (growing) economy and a stable currency shared with other countries and tied to euro.
A startup city would still be inside Senegal territory and be subject to Senegal immigration's laws.
Instead of spending 6 billions to build a one man vanity project, use those 6 billions to open a fund that guarantees loans requests by those people that do not have enough bank guarantees to access credit.
That's how you teach people to fish, IMO.