it's true, the matchmaker hates you.
without paying for a premium account, grinding to a higher tiered tank is slow and painful. I am lucky because I got to spend seven months playing the beta before the full release. during the beta I went crazy playing as many different tanks as I could before the full release wiped all my efforts away. So when full release rolled around, I knew exactly what tech tree branch to focus on in order to get those higher tier tanks.
if you're playing F2P like me and want to get into a higher tier tank, the trick is to discover ASAP what kind of tank you enjoy playing with the most and then focusing on that tech tree branch without exception. I'm not saying play with just one tank, but make one your main focus and never lose that focus or else you'll be puttering around in low tier tanks forever.
join a clan or get to be friends with someone that has premium so you can form platoons and play together. like most MMOGs, effective coordination and communication is going to see your team come out on top more often than not. playing solo is going to really draw the grind out even longer than necessary.
wish I had better advice for getting into a high tier tank, because part of the fun is figuring out what kind of tank(s) you like to drive. but the entire time you're finding out which type of tank floats your armored boat, it's all time wasted that could have been spent focusing on that one tech tree branch. you can research nearly every tier two tank for a nation after a couple of GOOD wins in the crapboxes. then it is a matter of saving up credits to purchase those tanks, driving them around for a few battles and discovering what really fits your play style. I can't emphasize enough how important it is to start focusing on a single branch ASAP. Especially for F2P players and people that WANT to drive higher tier tanks.
personally, I focus on the American heavies. that means I save every single free xp point for that branch's modules (spend free xp for modules only, NOT for researching tanks), and every credit I save is for the next American heavy. I researched the tier eight heavy a couple of days ago and I'd be driving it now if I didn't get side tracked by grinding out the Russian's tier six heavy (for free garage slots..free stuff is cool).
So yeah, you can drive a high tier tank with a F2P account. it may take you over a month like it did for me, but it is possible.
oh, another suggestion I have is to get a "money maker" tank for when you need credits. arty is a good money maker, but I don't like playing arty so I use the Easy 8 Sherman as my money maker. these money maker tanks are even more important as you get into the higher tiers, because the high tier tanks will NOT pay for themselves if you have a bad run of luck with many losses in a row. all premium tanks are money makers.