Clarify rules on Preview system

[nv-ananjappa]

Note that this does not change the rule. This PR only clarifies the Preview HW rules by rewording since we found the current wording as confusing.

If folks would like to strengthen or change the Preview HW rules, I encourage that to be a separate initiative since that is expected to take more time, whereas we want this particular PR to be merged ASAP to avoid confusion with the current understanding of the rules as they stand today.

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[mrasquinha-g]

The inference working group has approved this change.