In this day and age, probably with a relatively tiny investment into public access points, we could very reasonably have a technically functional direct democracy. The legislative cycle is already authenticated so there's no need to solve "authenticated anonymous vote" problem, European countries already have functional eIDAS systems to back the authentication part and the legislative systems are already to some degree digitized.
On one hand, the problem "what if someone sells their vote" is already present and unsolved, in the shape of lobbying. What's interesting, though, that we have built entire systems to shape public opinion and entrenched them into our daily lives, which are used by corporations and politicians alike.
This begs a question: is there such a thing as unbiased public opinion without authenticated internet access?
inb4: direct democracy does not mean parliamentary systems could be abolished altogether, central spaces for debate would still help solve discussion exchange problems