Matthew Kratter Says Bitcoin's Real Risk Is Who Controls the Blocks

Matthew Kratter of Bitcoin University joined the show, and he did not spend his time on the chart. His argument is that the thing most likely to hurt Bitcoin is not a bad quarter. It is the small number of companies that decide what goes into each block.

The concentration is the core of it. By Kratter's account, five or six entities now produce roughly 90 percent of Bitcoin's blocks. A Chinese pool, Antpool, and the operations clustered around it run near 30 percent of the hash rate. Foundry, based in the US, runs another 30 percent or so. When that few hands decide block composition, you do not need a textbook 51 percent attack to cause real damage.

THE BILL THAT COULD MAKE IT WORSE

Kratter's worry has a live policy hook. The Mined in America Act, introduced by Senators Bill Cassidy and Cynthia Lummis, would certify domestic miners, push them off foreign-adversary hardware, and let certified operations sell newly mined coins to a Strategic Bitcoin Reserve in exchange for a capital-gains break.

The framing is national security. The effect, as a piece in The Rage laid out, could be the opposite of decentralizing. Subsidies and reserve incentives reward the miners big enough to qualify, tilting the economics further toward the largest players. Once a miner runs on government incentives, those incentives come with conditions, and conditions are an attack surface.

THE FIX IS OLDER THAN THE PROBLEM

Kratter's answer is to put block construction back in individual hands, which is how Bitcoin was meant to be mined. He pointed to Ocean, the pool that lets miners build their own block templates rather than accepting one from the top, and to BIP-110, the contested proposal to limit arbitrary non-financial data that surfaced after Bitcoin Core's v30 release loosened those limits.

That governance fight is downstream of the same concentration. A small group of maintainers pushing through consensus changes is the software-side version of a small group of pools deciding what blocks contain. Kratter has moved his own hash rate to Ocean and runs Bitcoin Knots over Core for the same reason.

THE NUMBER THAT WORRIES HIM MOST

The data point Kratter kept returning to was not about pools at all. In 2025, for the first time, the share of people self-custodying their Bitcoin went down. ETFs and treasury products made it easy to own exposure without ever holding a key, and a lot of people took the convenient option.

His prescription was direct: hold your own keys and run your own node, because without one you are trusting someone else to tell you your Bitcoin is real. Bitcoin is not protected by physics the way gold is. It is protected by the people who choose to run it. Right now, fewer of them are choosing to.