[2020] This is terrible. Honestly bakkesmod is amazing and RL needs it.

Hi guys, we're looking into where this knowledge base article came from and why it's written this way. So please don't get the pitchforks out just yet.

Psyonix's position has not changed with regards to Rocket League. This article still represents it: https://support.rocketleague.com/hc/en-us/articles/360054229254-Can-I-use-Third-Party-Mods-with-Rocket-League-

We do not officially support the use of third-party software. Any inappropriate use of these applications, such as gaining an unfair advantage in-game, may lead to disciplinary actions.

edit: Fixed link, thank you heroic commenters for pointing out the relocated KB article. The URL changed when it got updated to be even more clear than before.