No, not in my opinion. They're closer, because as a starting point they're 4 people known to each other. And that is closer than 8 random people. That is a undeniable fact.
Those 2-4 friends that want to play together is a non issue. In my personal experience you'll not notice them over 8 totally random people. It is the "elite optimum-composition max-gear voice-comms SAS team" that stomp anything and everything that is a problem. If you've ever been one out of the randoms in such a premade, you'll quickly realize that PVP just turned into a joke. It's piss easy. No fun. And definitely no fun for the 8 randoms in the opposing team.
I'm not saying that they shouldn't create a proper matchmaking system. I'm saying they should immediately redo/remove the current situation with "premades". And that can't be done unless they remove the ability all together, or make certain that 2x4 people are matched up against 2x4 people. Premade vs premade in other words.
We have premade versus premade already, its called ranked warzones. It failed because it split the (small) pvp community in to two separate queues, making queue times longer (big negative) and highlighting the massive differences between good and bad premades to the point where all bad/average premades stopped queuing. You're suggestion has already failed, so I see no reason to repeat that failure.
For the record, we are after the same thing: fair pvp matches
However, your method has already failed (segregating the community) because it doesn't address the core of the matter - player skill. Player skill is amplified by gear and premades but ultimately player skill should be the ultimate balancing method, and a ranking system is the closest we can get to measuring player skill.
If we split premade and solo queues, I guaruntee that within a month the premade queue will be pretty much dead and the exact same problems we have now will still exist in solo warzones.