Outdated beliefs probably. When I talk about v6 support in our b2b saas, PM laughs and says nobody uses that shit. Big tech are massive laggards on this funnily enough.
Definitely not for the biggest ones. Google and Meta have so many machines in their data centers that IPv6 addressing becomes a technical necessity due to the risk of exhausting the RFC 1918 address space. Naturally, they were early adopters of IPv6.
Yeah, I can't imagine managing fleets like that with only v4. Our network config is so convoluted with gateways and NATs everywhere, paying AWS through the nose for it all, when it could all be so much simpler.