Even if you don't see formal unionization, the simple fact that there isn't someone more desperate for work forces a pretty high minimum standard for working conditions. As things stand with the 5% unemployment rate western nations target, the floor on working conditions is what's legally required, as there will always be someone willing to accept work for those terms. With 0% unemployment the worker can more or less choose what terms they'll accept, with or without formalized collective labor power.
Even if you don't see formal unionization, the simple fact that there isn't someone more desperate for work forces a pretty high minimum standard for working conditions. As things stand with the 5% unemployment rate western nations target, the floor on working conditions is what's legally required, as there will always be someone willing to accept work for those terms. With 0% unemployment the worker can more or less choose what terms they'll accept, with or without formalized collective labor power.