Avoiding commercial enclosure

Dilemma: any “open science” company or project without a deep + permanent commitment to remaining open and serving the public interest (via well defined stakeholders, charitable or public-institutional oversight) is likely to be acquired by a proprietary company. This usually results in closing off data, shutting down open projects, and creating profitable bottlenecks.

Dilemma: even academic or charitable efforts, if not designed with long-term fallback plans for maintenance and archiving, can either end up being acquired as above, or can simply shut down long before their hoped-for sunset period.

What are solutions to this that anchor themselves to existing century-scale initiatives?