Minimum wage is the bare minimum that you can pay people, most first world countries enforce a minimum wage. Conservatives like to argue that the minimum wage means that companies have to take on less staff if they can't afford to pay the minimum wage, although they forget that minimum being the bare minimum companies can pay is still a very low and it's only there to prevent companies from paying ridiculously small amounts to their employees, if the minimum wage was quite a high amount that it would obviously have a negative effect on the company.
According to the Pew Research Center on a report published on August of 2018, the real wages of Americans have not grown significantly over the past 40 years. The research shows that purchasing power stayed the same due to inflation, rendering the average wage increase meaningless in a way. However, people with substantially higher wages than average have seen their wages go up.
Without an increased purchasing power, many Americans are still stuck in a state of poverty, as prices continue to go up and wages not catching up. Some have argued that this shows a undeniable need to raise the federal minimum wage, Senator Bernie Sanders and many progressives have pushed for the increase to be moved up to 15 dollars an hour.