I saw Russian Ark! Definitely a piece of art made by film buffs for film buffs; impressive to see, but far more impressive when you understand the amount of work that went into it.
I'm wondering why people would have chosen to do early digital if it was so inconvenient. When did the cost and flexibility advantages start to really kick in?
So in the context of this specific goal—shooting a feature film in a single unbroken shot—digital was a pain in the ass, but this was close to impossible to do on film, and Russian Ark was the first to ever do it, on any medium.
Simply shooting a feature film digitally was not that complicated by this time, or at least it didn't have to be. The Sony CineAlta F900 was the camera developed to shoot the Star Wars prequels, and was revolutionary at the time, became the gold standard for years, and very convenient relative to film. Tons of things started to be shot in 1080p around that time, and it was very nice to work with. Collateral was insane because they wanted to shoot raw and at high frame rates. Russian Ark needed a single unbroken shot in a form factor that one human would be capable of holding for that long. Aside from very specific and/or boundary-pushing needs, the arrival of the F900 in 2000 was effectively when digital was more convenient than shooting film while also meeting the technical requirements of high-end production (though it was many more years before most cinematographers agreed that the image quality was comparable)