Yes, this is how I read this, too:
“Apple Creator Studio (…) includes (…) intelligent features and premium content for Keynote, Pages, Numbers, and later Freeform for iPhone, iPad, and Mac.”
Pages, Numbers, Keynote, and later Freeform will be free to use, but parts of its future feature set will require this subscription.
As always with subs like that: it is a good deal when you are using everything, and it is pricey if you do not use the whole Creator Studio (for the casual user). 
“Services revenue, services revenue, services revenue…” - 2025 marked a record-breaking year for Apple services - Apple 