That's probably never gonna happen again, and here's why.
The rated brackets for 2v2, 3v3 etc. weren't seperate when it came to the ladder. This is a huge issue when it comes to 3v3 specifically, because that bracket hands out titles. Level 70's, 80's etc. could therefore achieve glad, and even rank one titles, without having to face the actual glads and r1's of endgame players. It also meant that people who did play endgame could get titles robbed without even having the possibility to face the respective team(s). It basically made for overall bad pvp-design for multiple reasons.
People could farm "bads" in the twink brackets, then level to max level and be like "yo I'm rank one lul" etc. It had to be removed.
The only way I can see them re-implementing the ranked system for lowe rlevels is to make the ladders seperate, and hand out different titles/rewards for the lower brackets, but even then, that's something "more" they'd have to manage for a particularly low population of the game. Realistically, it's just not going to happen.