Digital doesnt have the same copies as physical copies. Physical copies is limited to how much they produce, while digital is just a key.
As for sales, digital sales tend to get cheaper after 4-6 month of the release windows. Especially during winter, holiday, spring, and summer sales. Only used copies are cheaper, which goes toward resellers, and not devs.
It was 60% digital and 40% physical. The lockdown increased the digital purchases. Which brings another key point.
Current situation affects physical copy sales alot. While digital doesnt suffer from this issue, which explains why digital is gaining momentum right now. Then add the game store closure all around the world, which makes physical sales even harder.