This is a good idea from the perspective of the customer, but it breaks the cross subsidisation model of packaged accounts.
Selling travel insurance to a million people, half of whom won’t travel is cheaper per person than providing insurance to half a million people all of whom will travel.
The idea being that if, say, three services are provided, and 90% of customers only benefit from two of them, the service providers can reduce the prices overall so that everyone benefits.
If customers are allowed to pick and choose, they’ll often be better off using a comparison website or trawling the internet for discount or referral codes.