Hi @SeanMcC thanks for your question!
The answer depends on what you’re hoping to get out of the segment. You could simply use the parameters “IS NOT suppressed for email” and that will include all active users on your list, even if they have previously unsubscribed but then resubscribed.
If you’re looking to find how many people have unsubscribed and then resubscribed, then I would make a segment where someone IS NOT suppressed for email AND has unsubscribed at least once over all time - that should give you people who have unsubscribed but are still emailable, either because they resubscribed or they took a different action putting them back on your list (like placing an order).
Let me know if that helps.