Backport slow count improvements and fixes to 1.17

[marseel]

What type of PR is this?
/kind feature
/kind bug

What this PR does / why we need it:
Cherry-pick: #1524 #1525 #1602
Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[k8s-ci-robot]

Hi @marseel. Thanks for your PR.

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[mm4tt]

/ok-to-test

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: marseel, mm4tt

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[wojtek-t]

Why this was backported?

[marseel]

I've backported it (whole custom thresholds) to not have merge conflicts, but it won't be used in our tests afaik