The point of Harley Davidson's move was to expand into 3,600 sq. ft. of space that became available at the Downtown Disney West Side.
That opened up Harley Davidson's old space for a new tenant, an Apricot Lane Boutique.
I don't see how any of this suggests the demise of Hyperion Wharf. The Pleasure Island brand is dead (although the old signs are still up, for now). The new name for that area will be Hyperion Wharf. The rebranding to Hyperion Wharf includes some cosmetic changes to the area, including demolition of some of the old structures at Pleasure Island. If outside companies want to invest in snazzy new buildings, Disney will be happy to let those companies spend money. If not, Hyperion Wharf will be little more than what's left of Pleasure Island, with a somewhat different look.
Current businesses and new businesses at Pleasure Island / Hyperion Wharf can stay open, even if there are some construction walls near them.
The success (or failure) of Hyperion Wharf will depend on Disney's ability to attract and retain tenants who are willing to pay what Disney wants and to put up with Disney's terms and conditions.
Landing national chains like Apricot Lane Boutique is exactly what Disney is trying to do with Hyperion Wharf.