Lol, the thing is, Splatoon is not like C.O.D, and all the regurgitated trash that has been coming out recently, it is extremely team heavy. You cannot just go out, get kills and ink the floor and think that everything is all just fine. You absolutely HAVE to look out for your teammates, because if someone dies, and you just go on about your merry way, that is an opening anyone worth their salt is going to take advantage of. Now, yes, sometimes you get a pretty bad match, such as being on a team with 3 chargers and a single roller, it sucks, but it's likely to only happen a few times throughout the day. And, as far as unranked matches go, you're not going to come across some godlike team made up of a bunch of S+ pros that are going to welcome you into their numbers. Children play this game too, regardless of how often we may forget this. However, losing 24 times in a row on 24 different teams comprised of a moderate amount of randomly selected players seems to have one common denominator. . . I'll be a little more subtle than everyone with their "git gud". :]
Point is, learn to support your team, because yea, you got 1200p, but the guys that got 700-600p weren't getting any of your support, clearly, and were likely getting killed, ganged up on, and is likely the reason you lost. Don't get me wrong, there are times where you'll get a crappy match up, which is likely to happen in any online shooter. however, blaming it on your entire 24 losing streak on entirely different randomly selected players seems a bit far-fetched. And from the outside looking in, seems to be pointing to you.
EDIT: Also, make friends that seemingly know how to play the game, and you'll have even less to blame your losses on. :]