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As widely publicised on Reddit, the review-bombing campaign began in response to the updated EULA, which reportedly grants Take-Two "root level access to users' systems, under the guise of anti-cheat software". As a result, users are concerned that sensitive information like passwords, IP addresses, and login details are being unfairly collected.
In addition to privacy concerns, the new agreement also raised fears in the game's modding community, with many users citing that targeting third-party applications could introduce unnecessary limitations to legitimate gameplay modifications.
While the uproar has noticeably impacted the game's review scores, the sentiment on whether the reaction is justified remains mixed. Some users argue that the new EULA borders on "spyware," while others highlight that it is not substantially different from the previous versions and that the updates largely align with industry standards.
Regardless, reviews for the games, which previously held a "very positive" rating on Steam, now vary between "mixed" and "mostly negative".
TL;DR: The Borderlands franchise faces review bombing on Steam due to a controversial EULA update granting Take-Two root-level system access, raising privacy and modding concerns.
Source - TweakTown