Bitcoin (BTC) spot-based exchange-traded funds (ETFs) could bring $30 billion in new demand for the world’s largest digital asset, according to crypto trading firm NYDIG's recent research report.

The spot-ETF fever has gripped the crypto market in recent weeks, thanks to filings by BlackRock (BLK), Fidelity and others.

“The brand recognition of BlackRock and the iShares franchise, familiarity with purchase and sale methods through securities brokers, and simplicity of position reporting, risk measurement, and tax reporting, a spot ETF could bring some noted benefits compared to existing alternatives,” NYDIG writes in its report.

Already, NYDIG has modeled that there are $28.8 billion in bitcoin assets under management with $27.6 billion in spot-like products.

Bitcoin is often called digital gold, so there are bound to be comparisons to gold ETFs listed in the early 2000s. Currently, gold ETFs hold only 1.6% of the total global gold supply, NYDIG points out, compared to central banks at 17.1%, while bitcoin funds hold 4.9% of the total bitcoin supply.

There’s a massive gulf in demand for the digital and analog version of the asset in funds: there’s over $210 billion invested in gold funds while only $28.8 billion in bitcoin funds.

“Bitcoin is about 3.6x more volatile than gold, meaning that on a volatility equivalent basis, investors would require 3.6x less bitcoin than gold on a dollar basis to get as much risk exposure. Still, that would result in nearly $30B of incremental demand for a bitcoin ETF,” NYDIG writes.

The newsletter Ecoinometrics has a more cautious take on a bitcoin ETF.

GLD ETF filled a significant void in the market, Ecoinometrics writes, providing an easily tradable product that tracked the price of physical gold.

However, comparisons between gold ETFs and bitcoin ETFs are potentially misleading as the significant rise of gold during that time was largely due to a favorable macro environment and a weakening dollar. Remember the war on terror, China’s rise, and the beginning of a ballooning U.S. deficit all packed into a decade?

"So while the GLD ETF definitely didn’t hurt and probably brought some nice inflow to the gold market, macro was really in the driver’s seat over that period," they write. "A spot Bitcoin ETF can help with drumming up more interest into Bitcoin and will undoubtedly attract some fresh money into the space. But that won’t make one Bitcoin worth $100k single-handedly."

The real potential for a Bitcoin ETF lies in a convergence of factors: the launch of the ETF, a weaker US dollar, a Federal Reserve move towards Quantitative Easing, and a generational wealth transfer to younger individuals more likely to invest in crypto, they write.