Yes, Freeform likely would only get the very niche market, just like Pages and Numbers. In the same way, they are not selling Freeform, just like how they are not selling Pages and Numbers. They are adding features across apple devices to sell more devices.Freeform may be regulated to the same very niche market Pages and Numbers has.
It's no secrete apple devices are overpriced. But with all the subscription based services, companies ended up paying $200~$300/user/year for the services. So with enough features from apple, the surcharges of the device might become acceptable or even preferred.
Sure Pages isn't MS Word, Notes isn't Evernote, or Freeform isn't Miro, but with each itty features added, companies will start reconsider maybe that's all they actually needed. With each bitty added, it becomes closer to the tipping point for someone to decide to switch.