When Players Only started last fall, it was billed as a unique NFT project, co-founded by Michael Carter-Williams, supported by other pro athletes, that would allow investors who bought its non-fungible tokens to interact with them in person and through the online community the project was building. But by this spring, the project had sputtered. Conversations on its Discord server — a voice, video and text digital platform, had slowed. An April AMA session centered on the project’s founders hearing out grievances from its NFT holders. A long backlog of giveaways built up.