What is structured content, really?
Structured content means content that knows what it *is* rather than what it *looks like*. A product description with separate fields for name, features, specifications, and price is structured. A product description pasted into a WYSIWYG editor as a blob of formatted HTML is not — even if it looks identical to the end user.
The compounding cost of unstructured content
Unstructured content doesn't cause pain immediately. It causes pain at the point of change: when you replatform, when you add a new channel, when you try to localise, when you want to personalise. Each of these operations is cheap if your content is structured and expensive — often prohibitively so — if it isn't.
The argument for acting early
The right time to structure your content is before your first migration, not during it. The earlier you define your content model, the more data you have that conforms to it. Every month you run with unstructured content is another month of technical debt that will cost real money to pay down.
Start small
You don't need to model everything at once. Pick one content type — product descriptions, event listings, team members — and model it properly. Establish the pattern. Let the team see what structured content feels like to create and maintain. Then expand. The compounding benefits show up quickly once you have a template to follow.