Marketing campaigns vs. email marketing journeys: When to use each for customer engagement?

I’m trying to determine the best approach for our marketing operations in D365 Sales 9.0. We have both the classic marketing campaigns module and the newer email marketing journeys capability available. Our team is split on which to use for different scenarios. Some prefer campaigns for event promotions and product launches, while others advocate for journeys for nurture sequences and drip campaigns. The engagement tracking seems different between the two, and I’m concerned about module integration complexity if we use both. What are the practical differences in terms of campaign vs. journey use cases? How do you decide which tool to use for specific marketing initiatives? We need a clear strategy that maximizes customer engagement tracking without creating operational overhead.