Disable bottom-level bloom filters to save memory

[flyingsilverfin]

What is the goal of this PR?

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• describe the new product behaviour in present tense, and the old behaviour and how it's been changed in past tense.
• Use the Royal We: "We" made changes, not "I" made changes. }

What are the changes implemented in this PR?

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• its responsibility,
• how it's expected to behave, and
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