Person associated with multiple opportunities

If you want, you could further add constraints to the Added/Updated Opportunity trigger/filter so you only let a person qualify for a particular revenue stage update campaign/transition. In case there are multiple opportunities, but w/o any such constraints, a person with more than one opportunity would just need to have only of one of the opportunities such that it qualifies for the RCM stage update campaign/transition. In a nutshell, yes, each opportunity add/update is a viable trigger/filter for the lifecycle campaigns/transitions.

If you've additional filters added to the revenue stage update campaigns/transitions, so that a person already in RCM stage x cannot flow for it, then the person already in suppressed RCM stage won't flow through it, even though they got their opportunity updated to the opportunity stage corresponding to the campaign. e.g., The "Open Opportunity" revenue stage update campaign can have a filter so that people already in the "Closed Won" revenue stage cannot qualify, in that case, a person with at least 1 Closed Won opportunity associated with them would not qualify for the"Open Opportunity" campaign even though a new opportunity record with correct corresponding stage is associated with them.