Putnam is a good way to set you apart and is something that will catch my eye when looking through a resume; it especially helps make up for being from a non-target. If you want to break into quant trader specifically, coding is less important compared to other roles such as QR or QDs. However, I wouldn't recommend 'doing nothing but grinding Putnam for 3 years'; there's opportunity cost to that. It's better to focus on grinding on getting a quant trading internship and getting in the industry that way. For context, I was also AIME level in high school and my undergrad probably had less name value than a T50 non-target yet I still broke into a top quant trading firm (think JS/Cit Sec/Sig) without Putnam (although I do regret not doing Putnam as I think it would have made my job hunt easier)