Crypto’s House of Cards: Stablecoins, Altcoins, and Memecoins – Are They the Subprime of 2025?
“History does not repeat itself, but it often rhymes.” — Mark Twain
Inside Job, Charles Ferguson’s Oscar‑winning documentary, opened millions of eyes to the way a seemingly small slice of risky mortgages triggered the 2008 global financial crisis. Subprime mortgage debt was around US$1.3 trillion at its peak – only about a fifth of the U.S. mortgage market – yet when the economy slowed and defaults spiked, that slice catalysed a cascading financial panic. Banks failed, money‑market funds “broke the buck,” and the global financial system needed extraordinary support to survive.
Seventeen years later, a new multi‑trillion‑dollar edifice has sprung up on top of the modern financial system. Bitcoin, Ethereum, thousands of altcoins and memecoins, and a growing roster of so‑called stablecoins now represent about US$4 trillion in market value[1]. Supporters promise that these digital assets will democratise finance. Critics see a house of cards built on leverage, speculation and regulatory blind spots. As the U.S. Congress attempts to tame part of this market with the GENIUS Act, this article asks: Are stablecoins, altcoins and memecoins the subprime of 2025?
From Bitcoin to Memecoins: Building the Crypto Stack
The crypto economy isn’t a single block of value; it’s a layered stack of assets with very different risk profiles. Understanding the size of each layer is essential for comparing today’s market to past crises
1. Bitcoin – the base layer. Bitcoin remains the largest digital asset, with a market value of roughly US$2.24 trillion, accounting for 56.43 % of the entire cryptocurrency market[1]. It functions as a store of value and is widely held by institutions.
2. Ethereum – the smart‑contract layer. Ethereum’s market capitalisation hovers around US$550 billion[2]. It powers a huge ecosystem of decentralised applications and tokens.
3. Altcoins – everything other than BTC. Analysts estimate that altcoins collectively amount to US$1.5–1.7 trillion, representing ~44 % of the total crypto market[2][3]. This category includes smart‑contract platforms (Solana, Cardano), DeFi tokens, AI coins, gaming tokens and myriad other projects. Most have little or no revenue to back their values.
4. Memecoins – joke coins turned serious money. Memecoins began as internet jokes, yet by 2025 they hold US$80–90 billion in value – 5–7 % of the entire crypto market[4]. Dogecoin and Shiba Inu remain leaders, while Solana‑based tokens like Bonk and dogwifhat appeal to traders seeking viral gains[4].
5. Stablecoins – the “money‑good” layer. Stablecoins are digital tokens pegged to fiat money. As of September 2025 the total stablecoin supply stands at about US$297 billion, roughly 7.5 % of the entire crypto market[1]. The vast majority are pegged to the U.S. dollar and used for trading and payments. Tether (USDT) alone accounts for ~US$170 billion.