I know many engineers that want to unionize. It's not that hard to convince people once they stop drinking all of the anti-union kool aid that has proliferated in the US over the last several decades.
Look at pro athletes that are contracted under a CBA. They get to negotiate profit-sharing, minimum salaries, guaranteed raises, etc. Roughly half of the revenue generated by the NBA is allocated to player wages.
Apple generates somewhere around $1.9M per employee[0], with a median salary just shy of $160k. One of the most common criticisms of unionization is that it would cap salaries and people would earn less. If Apple employees were compensated like basketball players, the average salary would be somewhere around $1M.
0: https://www.emergingtechbrew.com/stories/2020/08/12/ranking-...
0% to even lets say 50% instead of "all" in 10 years is just not possible. The "valuable" employees (engineers) for these companies don't even want to unionize. You'll have to convince them that somehow it would work out in there favor before you could even start the effort and that would take years alone.