51% of all participating voters has to reject the pardon to prevent it. Further, the pardon’s effect is restricted to their state. A presidential pardon is national, but again requires 51% of participating voters to deny it.
Who are the voters in this scenario?
EDIT:
we should have open-sourced digital and standardized direct voting on all matters
First of all: digital voting is famously difficult to pull off. Source: last two US elections, especially the 2024, where - somehow - the guy who's friends with the guy whose company makes the majority of the voting machines, and who provides them all with Internet access, somehow knew the result 4 hours before the count ended.
Secondly: direct voting is probably the worst thing you could think of in terms of systems of governance.
Just think about it - all the flat earthers, all the anti-vaxers now get to vote in critical, strategic things. You get idealistic pacifists to vote on the military budget, and people who failed primary school to vote on the NASA budget. Laws are famously convoluted and full of tech- and lawyer-jargon, and you want to have Buck and Darlene from the trailer park voting on them?