This contribution examines the limits to financial expansion relative to the real economy, analysing the substantial growth of financial assets from the 1980s through the 2020s. We document how policymaking activism sustained financial expansion beyond the 2008 GFC, creating a puzzle given theoretical expectation of periodic deleveraging. The early 2020s inflation outbreak provides a crucial test case for understanding monetary constraints on financial system support. Drawing on Minsky’s financial instability theory, BIS financial cycle analysis (Borio), and the Marxist concept of fictitious capital, we develop a comprehensive framework for analysing these dynamics. We document the Supercycle’s evolution from 1980-2024 across four North Atlantic economies using a fictitious capital indicator and principal component analysis. Our analysis reveals three distinct phases: long neoliberal expansion (1980-2007), state-sponsored General Ponzi (2008-2019), and inflation-constrained retreat (2020-2024). Contrary to expectations, no shrinkage occurred during the 2010s as central banks sustained expansion through asset purchases and balance sheet growth. However, the post-COVID inflation period marks a decisive halt, with financial assets contracting relative to GDP. We theorize these constraints through the Non-Asset Busting Interest Rate (NABIR) framework, which formalizes the tension between price stability and financial stability objectives. When inflation forces interest rates above what leveraged financial systems can sustain, monetary authorities face impossible trade-offs. Our findings suggest that financial repression through controlled inflation may enable orderly downsizing of oversized financial systems, with implications for the future of finance-led accumulation regimes.