Baseball has a very difficult road ahead with African American athletes. Aside from any draft changes that results in less picks, it's marketing too. When you see black athletes in basketball and football, they are household names with huge social media followings. That's what young people today grow up on. Branding is very profitable, and baseball players just don't have it. Mookie Betts should be one of the biggest stars in baseball marketing considering he's not only great and black, but also easily relatable due to his size. Yet put a video of Mookie on ESPN's YouTube page and it gets less views than practically every other piece of content they put out there. Tim Anderson just won the batting title but no one outside of Chicago knows who he is. And so on. MLB doesn't have to worry about Latin America since baseball is life over there, but in the US/Canada, they have a real issue with athletes (black or otherwise) and are not helping themselves.
When it's not cool to follow baseball, and now MLB itself is making it harder to even make it to the league, it's just going to discourage more athletes from even trying. I hope the participation rates remain high in young kids, and the dangers of football make that sport less desirable, but MLB has no chance of catching the NBA (fanbase is very young), and the NFL is still king in the US from a popularity standpoint with no end in sight.
MLB has to fix its brand. Manfred isn't helping, but if it becomes cool to watch baseball again, then the athletes will follow, IMO.