If we keep up the 330k per month, that would be a 2.4% increase in jobs in a year. There is no way that the workforce can increase by 2.4%, especially with the Baby Boomers retiring. The main constraint on the current labor market is a lack of labor. If we had more people looking for jobs, we would be able to fill more jobs.
"Labor utilization" is not a macro economic number. Could you be thinking about labor participation? Labor participation is not at an "all time low." Its overall trend is dropping with an aging America, but before women joined the workforce in large numbers, it was much lower.