I personally think this is mostly an annoyance, the maximum time is 24 hours anyway. I don't see any benefit from this change, but I'm always up for discussion if anyone feels they know why this would be a good thing.
Playing devil's advocate here:
/r/politics is one of the most prominent subreddits that does this. /r/AskReddit also does this.
AskReddit has a one hour timer on this. Politics has much longer timer (something like 2-4 hours? I'm not sure).
There's an old post in AR that covers the motivation behind implementing this:
The goal of this feature is to try to reduce the initial bandwagon/snowball voting, where if a comment gets a few initial downvotes it often continues going negative, or vice versa. By hiding the score for a while after posting, the bias of seeing how other people voted on the comment should be greatly reduced.
In /r/magicTCG, you might want to give people an hour buffer to discuss new ideas that may not be initially well met. If people don't see scores in the first hour, they may be more receptive to hearing opposing sides of a debate.
If someone makes a thread:
"What cards should be banned in Modern after PTOGW?"
The first two replies might be "Eye of Ugin should be banned" and "Let's not ban anything after just a single event."
If two people who both play Modern and have a deck with a weak matchup against Eldrazi see these two posts, they may very well both downvote the second comment and upvote the first coment.
Now, any future readers seeing these posts might be more likely to think that banning Eye of Ugin is the best solution and taking a wait and see approach is bad, just by virtue of seeing one comment sitting at +3, and the second at -1. Maybe there's even two people who want to comment on the -1 post. One guy tries to defend that position and he gets downvoted and it's immediately visible. Now, we have a train of downvoted comments and the effect may snowball even harder. A second guy jumps on the other bandwagon and replies "Banning Eye of Ugin is the only fix. I don't know why you think that doing nothing helps a broken format."
He downvotes the -1 to -2 and is immediately validated that his position is correct.
But, we've seen just 3 people change the whole course of the conversation and further discussion may just polarize opinions when everyone can see the scores immediately go up and down.
By having a one-hour wait, people can't just see what's popular, but have to judge comments on their own merits and some people might be more willing to say something like, "I think that waiting isn't the same as doing NOTHING. It's just being scientific and wanting more data so that rash decisions aren't made based off a single data point."
I personally don't know if it would make much of a difference, but I think this is the motivation behind people who would like it if the moderators instituted a wait on seeing comment scores in this subreddit.