I expect it will be a part of a negotiation tactic. The message would be along the lines of ‘you can self deport in 30 days and take all of your wealth and assets, if you’re here in 30 days everything will be confiscated and you you’ll be charged and jailed before you’re deported’. Or whatever message they think best resonates.

Think of the way they pushed the covid vax by steadily increasing pressure. The first few months they gave it to the die hards that wanted it. Then they started bribing those who were on the fence with gift cards. After that they moved to outright firing people and ruining their lives. If they’re serious about deportations they’ll do the same thing.