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New UEFI vulnerabilities send firmware devs industry wide scrambling
(arstechnica.com)
This is a most excellent place for technology news and articles.
A lot of the world, especially Africa and south America, was somewhat later in adopting the Internet and has a much smaller supply of IPv4 addresses. People with ISPs there need IPv6 to be directly connectable without CGNAT
For private address space you never need 6.
If you want to be able to connect to IPv6 services in the Internet you do.