meta: I will update this answer if new ideas come to me; I'm not actively thinking about this, I just want to document ideas I have despite not trying to think about it

quality: low

epistemic status: I think most/all the following ideas are not worth pursuing, and could even be net negative even without taking into account the opportunity cost. things that reduce friction to communicate with other languages can reduce the incentive to learn a more universal language and vice versa ; I'm not sure what's the right balance (75% sure it's the former)

Note: reverse all the following if you think the global communication index should be decreased

• Increase the number of international student exchanges
• Make (/incentivize making) stories in English appealing to culture not speaking English
• Reduce friction for temporary work visas
• Improve translators
• Reduce the number of content available in other languages (to increase the incentive to learn English
• Push social networks to be adopted globally (instead of having different social networks in different countries)
• Advocate for using English for the EU, UN, and other international communication
• Support policies that allow children to receive education in English if they want (especially in a region that is part of a country speaking English, but itself doesn't have English as its main language)
• Have every language adopt a similar spelling (with letters use for similar phoneme) to make it easier to learn other languages
• unlikely to work (and even likely to backfire if only partly adopted), but interesting idea someone just told me