Was the owner just trying to state facts or were they trying to swing the local election by threatening employees? I think in your example case, no, the owner would not break the law by just saying the business will shut down.

A few scattered, merely-the-facts statements that a business will shut down as a result of a new law is very different than a continuous campaign of political messages and surveys through the official work app. There's a lot more room to argue that Uber's communications amounted to an attempt to coerce or influence, though it will still probably be an uphill battle.

(I am not a lawyer)

There's no "I'm telling you the truth I'm really going to fire you" exception.