I would treat McKinsey Forward primarily as a learning and development program rather than as a direct recruiting credential. Completing it can give you useful skills and a legitimate connection to the firm, but it should not be viewed as an interview guarantee.
The value comes from what you actually gain from the program: structured problem solving, communication tools, and potentially a better understanding of how McKinsey approaches work. Those can help you prepare for future applications.
On a resume, the program can be worth mentioning if it is relevant and you have space, but your academic or professional achievements will still carry much more weight in the hiring decision.
If you want to recruit later, use the program as one input into your preparation and network, not as a substitute for building a strong overall profile.