I agree, as an athlete, Manny can promote a project to others rather than making coins in his own name. A coin created should be based on projects and products not from a famous celebrity's name or figure.
Perhaps the communities of athletes and famous people need to agitate them to start using Bitcoin? This will be the best advertisement for Bitcoin and all cryptocurrencies, increase the number of Bitcoin users and make it much more popular than today. But such stocks must be massive otherwise we wont get a big result.
We can't expect that it will happen instantly, Manny being one of the famous athlete in the world are getting involve in crypto is a good sign.
Of course, he would also market his coin to the boxing community and since he is still actively fighting and a very popular boxer, he could influence the boxing industry, actually people just need to be educated to see how useful crypto is and I think this requires time so let's be patient.