A marketing ecosystem is the set of connected places where customers discover and judge your business: Google Search, Google Maps, AI assistants, your website, reviews, social and video, and paid ads.
“Connected” is the important word. Each piece shares one set of facts (who you are, where you are, what you offer), one message and one way of measuring results. So a great photo shoot also feeds your Google profile, your website, your ads and the answers AI gives about you, instead of living and dying as a single Instagram post.
Customers do not experience your marketing as channels. They ask a question, see a few names, check reviews, glance at your social, and choose. The ecosystem is how you show up well at every one of those moments.