The argument that follows is not theoretical. It draws on a February 2026 survey of 509 active equity portfolio managers, the most comprehensive study of its kind; on the empirical record of carbon markets across three decades and two instruments; and on academic work in ergodicity economics that explains the monetary mechanism behind sustainable finance's structural limits.
The February 2026 working paper Sustainable Investing in Practice: Objectives, Beliefs, and Limits to Impact (Edmans, Gosling & Jenter — London Business School, LSE, ECGI Working Paper Nº 1028/2024) surveyed 509 active equity portfolio managers globally.
Its headline finding — 27% willing to accept even 1bp of return sacrifice — is striking. But the deeper finding is more important: sustainable and traditional funds are statistically more similar than different. Both mostly prioritise financial returns. Both use environmental and social data primarily when they believe it helps manage downside risk or improve expected returns. Impact motives — such as changing a firm's cost of capital or rewarding better behaviour — rank last among drivers of stock selection and voting. Even among "sustainable" funds.
The paper also finds that 72% of investors say environmental and social constraints changed their behaviour — and for a large share, those constraints reduced expected returns without producing commensurate real-world impact. Some constraints prevented investors from owning or engaging with laggard firms whose performance they believed they could improve.
The authors conclude explicitly: "The asset management industry is unlikely to lead the charge in improving the aggregate environmental and social performance of firms" under current rules.
The global carbon market experiment has run long enough to produce definitive evidence. The Clean Development Mechanism, the Voluntary Carbon Market, the EU Emissions Trading System, and Article 6 of the Paris Agreement represent successive generations of increasingly sophisticated carbon instruments. Each generation addressed weaknesses identified in its predecessor.
The result is consistent across all four: correction layers applied to an unchanged core system cannot override that system's structural incentives.
The Swiss case is the most important in the record because it was conducted under optimal conditions. The most committed Article 6 participant, with the most sophisticated implementation infrastructure, in the most favourable regulatory environment. 0.04% of the target. The conclusion drawn from this record should not be: Switzerland needs to try harder. It should be: the paradigm itself is the problem.
For full technical treatment of the carbon market failure analysis, see the dedicated resource at carbon-stewarding.harmoniq.world ↗.
Academic work in ergodicity economics (Gross, Blomsma & Boyd, 2026; building on Ole Peters and the London Mathematical Laboratory) identifies a deeper mechanism behind sustainable finance's limits: the financial layer commits an ergodicity error.
Standard financial theory assumes the future is predictable and endlessly repeatable — that historical return distributions will continue to hold, that compounding growth is permanently sustainable, and that tail risks are correctly priced. This drives investors to demand rapid, extractive returns to cover losses from systemic volatility. Which actively destroys the cooperative, long-horizon infrastructure that a sustainable economy requires.
The ergodicity correction requires redesigning the monetary OS itself — not adjusting portfolio preferences within it. Gross et al. argue that material circularity will keep failing as long as the financial layer is linear and extractive, because linear capital structures recreate linear resource flows. This positions the required intervention at the level of the reserve asset and the solvency definition — not at the level of fund mandates.