Why No IPv6?
IPv6’s slow adoption, despite being the long-term successor to IPv4 with vastly more address space, is attributed less to technical feasibility and more to economics, inertia, and risk-averse business priorities. Commenters argue that IPv4 workarounds like NAT and carrier-grade NAT have masked scarcity but at the cost of breaking end‑to‑end connectivity, hindering self‑hosting, increasing operational complexity, and driving up the price of IPv4 addresses. While some large networks and mobile carriers are moving toward IPv6‑first or IPv6‑only architectures, many services remain IPv4‑only because dual‑stack support adds cost without obvious short‑term benefit, prompting calls for regulation or stronger customer pressure to shift the ecosystem.
Regulation vs. market forces
- Some argue IPv6 should be mandated (e.g., by governments or the EU) to fix market failures and prevent ISP/cartel pathologies.
- Others see this as overreach and insist economics should drive adoption: when IPv4 becomes too expensive or constraining, companies will move.
Business incentives & IPv4 economics
- For many organizations IPv6 brings little immediate, visible benefit: IPv4 “still works,” so IPv6 gets deprioritized or killed as “not a priority.”
- IPv4 scarcity is real: public addresses are expensive, being bought and rented like real estate; some hosts and clouds charge extra per IPv4.
- New/small ISPs and community networks report high costs and delays acquiring IPv4, forcing investment in translation/proxy gear.
Technical design and complexity of IPv6
- Critics say IPv6 tried to “rewrite everything” instead of just enlarging the address space, introducing conceptual and implementation complexity (SLAAC vs DHCPv6, renumbering, no NAT-by-default, different local-network behavior).
- Defenders counter that NAT was a hack, IPv6 routing is still simple prefix routing, and address autoconfiguration is, in principle, simpler than IPv4+NAT+DHCP.
Deployment, tooling, and dual-stack pain
- Dual-stack is seen as a major burden: sites must support both but can’t yet drop IPv4, so IPv6 feels like extra work with no payoff.
- Many consumer/SMB routers and ISP stacks handle IPv6 poorly or inconsistently, causing weird breakage; this reinforces the perception that IPv6 is “buggy.”
- Chicken‑and‑egg: ISPs don’t push IPv6 because few sites require it; sites don’t enable it because most users are fine on IPv4.
NAT, CGNAT, and end‑to‑end connectivity
- Some praise NAT as a proven scaling and security tool; others see it as a disaster that broke end‑to‑end connectivity and forced centralized, workaround-heavy designs (STUN/TURN, P2P issues).
- Carrier‑grade NAT (and IPv4 exhaustion) already harms users: hard or impossible home hosting, double‑NAT, degraded performance, worse scraping detection, and higher infrastructure costs.
Adoption status and attitudes
- Supporters note substantial and growing IPv6 traffic (especially mobile, some large networks going IPv6‑only internally) and working transition techniques (NAT64, DS‑Lite, 464XLAT).
- Skeptics point to ~two‑plus decades of slow progress, lingering ISP/router issues, lack of consumer demand, and the fact that many major services still function fine on IPv4 only.
- Overall tone: recognition that IPv4 is finite and increasingly contorted, but deep frustration with IPv6’s deployment complexity and incentives misalignment.