Therefore, it is realistic to have a gradual burning over a long term of two or three years

1. Supply Shock
When the world wakes up to find that trillions of currencies have disappeared, leaving only 10%, there will be shock. The platforms will ignite, and orders will jump into the thousands per second. This sudden shortage in supply combined with the "ferocious" demand you speak of will cause prices to leap vertically (Parabolic move).
2. The entry of "smart money" and institutions