The largest male yellow that I have seen a record for taken in its natural range was right at 8 feet. In captivity, the upper maximum size limit for a male yellow is probably close to 10 feet. Male greens in their natural habitat average between 8 and 10 feet as adults with exceptionally large ones approaching 12 feet. The upper size potential for any male green in captivity is probably between 10 and 12 feet. Regarding male anacondas, captive specimens usually run slightly larger than their wild counterparts in most cases. I have a male green that just turned 3 years of age, which is currently right at 9 feet. He was fed fairly well during his first 2 years, but since then I have reduced his feeding to one large meal per month to avoid any obesity issues. It will be interesting to see his growth trajectory of the next few years. So you are correct in that you don’t see the size disparity between male yellow and greens that you see between the females of each species.
Kelly