This is a variation on an older question, with different wording to attempt to illuminate an alternative perspective.
A donor-advised fund (DAF) is "a charitable giving vehicle administered by a public charity created to manage charitable donations on behalf of organizations, families, or individuals." The sponsoring organization of a fund—often a subsidiary of a brokerage firm such as Fidelity Charitable or Schwab Charitable—is a 501(c)(3) registered charity that accepts tax-deductible donations from the creator of the DAF. The creator can then make grant recommendations to the sponsoring organization.
Sponsoring organizations legally own any donated money, and have no obligation to abide by grant recommendations. There have been cases in the past of DAFs refusing to use donated money as directed or using donated money for its own benefit. To my knowledge, no large reputable DAF has ever done this.
What percentage of money held in all US DAFs will be expropriated by 2100?
Funds are considered expropriated if:
- The DAF refuses to make a grant recommendation, insofar as the grant recommendation is legal.
- The DAF spends donated money on purposes other than a donor's recommendation, not including ordinary account expenses.
- The DAF begins charging unreasonable expenses (e.g., a 5% annual fee).
- An outside party, such as the US government, seizes control of all or a substantial portion of the money (including by taxation).
The following situations do not qualify as expropriation:
- The US government imposes a distribution requirement, such as the 5% annual distribution requirement that foundations must follow.
- The DAF refuses to abide by a grant recommendation because it legally cannot, e.g., because the would-be grant recipient is not a 501(c)(3).
- The DAF forcibly closes (e.g., due to Fidelity Charitable going bankrupt), but lets donors decide how to grant all remaining money.
 Article is paywalled, but the gist is that the Jewish Community Foundation of Los Angeles refused to comply with a donor's request to donate to a charity supporting Palestine.
 At present, Fidelity Charitable charges a 0.6% annual fee. Most other DAFs charge similar fees.