Hi IshGish, the above answers are technically correct but realistically this is something we need to fix. Thanks for pointing it out.

In fact, as soon as you complete a single turn you'll have that 100% RR and be able to join any public game (that you have the points for)!

You can play a single turn of a bot game, cancel/concede, and then join the 3% game.

I don't think I really need to post this, but I figure while I'm here I may as well post the screenshots to show what I'm seeing.
https://imgur.com/a/E6milZY

First is my profile and its 100% RR.
Second is a 3% RR game that I cannot join.
Third is a 1% RR game that I can apparently join but need a code for.

Made an account recently to play recently but nearly every game says I don't have a high enough RR to get in despite being started off with 100%. The only game that says mine is high enough is actually a 1% RR game. So, either the current rating isn't being used correctly or my starting RR isn't actually 100%.

My suggestion being an outsider would be to give a basic level of RR to start off with that's independent of a player's true RR until some number of games or turns can be run. I've also heard the game holds onto CD's for a year, which seems like overkill, and combined with people saying turns with bots can elevate your RR this system seems like it needs a lot more work.