The short answer
An extension is part of a name's meaning and practical use. IANA identifies .ai as Anguilla's country-code domain and .si as Slovenia's. AI and superintelligence associations are commercial interpretations, not changes to those official identities. Choose by audience understanding, the complete name, and verified registration terms.
Your decision checklist
- Read the full name aloud.
- Test how the intended audience interprets the suffix.
- Verify eligibility, renewal price, and premium terms.
- Compare the same concept across more than one extension.
- Keep a trendy association separate from evidence of buyer demand.
A practical example and next step
A clear .com phrase may fit one business better than a forced acronym ending; another audience may understand .ai naturally. SI as superintelligence is a thesis to test, not proof of resale value. Create alternatives and explain the trade-offs. Do not call an extension inexpensive until you have a current renewal quote.