Thank you for asking a question, first of all.
When the workers own and run companies, they are far more likely to give staff a better wage, as they themselves are the staff, and therefore have a vested interest in being paid better. They don't have to pay a CEO or pander to shareholders, either, and, with every single person in the company having a say on how the company makes and uses its profits, there is statistically more chance of the company being moral, and giving better company benefits like pension contributions, etc.
That, in itself, would raise your standard of living, but I'll give you some more.
Because wealth is then being more evenly distributed, and because there is statistically more chance of companies being more ethical, you will see far less homelessness, you will see far less child labour (because labour will be kept inside the country, to keep staff employed), far less unemployment, less tax evasion, less chemical dumping (like with fracking), more green energy use, etc., etc. which has a direct impact on that society's standard of living.
It's quite simple.