But we've just established in this thread that even senior people are having difficulty findings jobs. This has nothing to do with desperation. Temp contract works both ways, if an employee doesn't like the company or finds another job within the 2-3 months, they are free to leave. This is more than fair.

Ignoring that this seems like a bad way to start a hopefully long-term relationship, this would largely limit your pool to people who don’t already have a job. If a senior candidate already has a job, why would they give it up for a sketchy 2-3 month contract and the vague promise of full employment?

Relationships between an individual and a corporation are fundamentally asymmetrical. They can only be made equal by heavily favouring the single human side.