That's because people fundamentally misunderstand what matchmaking ranks are supposed to be about. They're supposed to be a rough measurement to match you to people who are roughly equivalent to your skill level, not measure how good you are overall. It's structured so that there aren't extreme differences in skill level.
So for example, my Zelda is roughly in the 8.40 mil. range. With rare exceptions, I'm matched with people within 50,000 GSP above and below me. So if we isolate that within a 100,000 GSP section, I would be in the middle of that. I'll lose more GSP if I lose to people in the lower part of that 100,000 and gain more GSP if I win in the higher part of that 100,000 or the inverted where I'll get less GSP if I win against the lower and lose less if I lose against the higher.
Is it the most accurate measurement? Probably not, I tend to go fairly even with those 50,000 above me, but get janked often enough by lag or other things to keep me at my current placement. But it is accurate enough to prevent me from three stocking some dude in the 6 mil. range. And that's really all this mode is meant to do.
The problem with most MM ranking systems is that they don't make the ranks vague enough and tend to label them in a way that gives the appearance of ranking people relative to the population on the whole, instead of relative to their peers in experience. It should be something like Beginner/Adept/Advanced/Master instead of 1/2/3/4 or Bronze/Silver/Gold/Platinum. The former gives off a difficulty ranking quality, much like when one selects a difficulty mode in single player games. The latter two gives off a status vibe and is why people start tying their worth as a competitor so heavily to something that isn't supposed to measure that.
Ultimate had the right idea by declining to implement a leaderboard for ranked mode and making a separate tournament mode for those seeking measurement against the general populace. They just flubbed the execution by making rankings too vague and giving visual representation to declining and rising GSP, and made goofy and uncompetitive rulesets for tournament mode. Had they expanded the Elite concept and made various modes like that while hiding the actual rank numbers and made a competitive section for tournament mode based on the currently agreed upon competitive rules, then online would be a lot better in that regard.
That's why it's ultimately pointless to try to game the system and why I sympathize with Oz's frustration. All it's going to do is put you against players far better than you and they will correct your rank to where it should be. It's like trying to skip directly to an advanced music course or something to that effect. You'll just be completely lost at what to do and ultimately leave in embarrassment.