Yeah, I don't see any consequences to voting "Yes", to be honest.
Basically the only people who dislike this new change are the highly ranked players who fear losing their highly ranked position.
According to the official thread, posted by the MCSG higher-ups, the old statistics will stay. Wouldn't that keep the highly-ranked players happy?
The reason they're still pissed off even the Legacy Leaderboards - where all of their hard work was permanently stored, although it means that nothing changes, those old leaderboards would be rendered pointless by several members of the community. The newer, more frequently updated leaderboards would be everyone's main priority, as the Legacy Leaderboards would only host memories.
As Gears mentioned, there is no need to fix something that is not broken. Although he may be correct as of now, the never-changing leaderboards will only continue to worsen. After only two years, the leading amount of wins has exceeded 4000. Imagine what the leaderboards will look like if the same trend continues - there will never be any change.
The joys of the leaderboard update is the fact that, as far as we can tell, there will be no end. Two years of data archived? No problem. After two years, we will see similar statistics, and they will only continue to grow. On top of that, we'll be seeing daily, weekly, monthly, yearly (etc) leaderboards, only adding reason for people to actually play the game competitively.
My main account has roughly 500 wins. It's honestly not that many, but I can definitely let go for the greater good of the community. With the merging of the AntVenom Network, the new players need a chance to make themselves known. They most likely had leaderboards as well, and had players at the top. It honestly just wouldn't be fair to not give them a chance.
(My post on a different thread.)