Well, theres this to go by:
Trust spam isn't allowed. If I see anyone posting dozens of fake trust ratings (from one account or many alt accounts), I will delete all of their ratings <
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I agree that it is a little annoying to see a wall of negative ratings, but this is in the "untrusted" section. The way things are set up currently, untrusted ratings can be easily spammed in a number of ways. That's why those ratings are hidden by default.
The quote is from 2014, so its a long standing complaint that crops up every now and then due to childish retaliation feedback, or spamming otherwise on the Trust feedback.