That is to say, provide email services that don't mine data for profit. Provide a social interaction space that doesn't attempt to manipulate moods, opinions, or sell its user's eyeballs. Provide an aggregation service with strong filtering tools in place of strong moderation. Provide a code repository with great tooling that doesn't include value judgements. Provide anonymous, secure communication between parties. Make mobile applications that provide wanted services without the in-app purchases, ads, or profiling.
The downside is that you're unlikely to get paid for it. You'll probably even lose money on it. In some cases, you'll even face legal pressure to stop or change.