I wish they didn't go with integrated PSUs. I don't trust anything other than server PSUs to deliver that amount of power without being electrical and fire hazards.
Ja. However, the integrated PSU's are a large part of the better efficiencies we are seeing from the new miners so that will remain the trend.
Even the best switching regulator designs are only pushing 98% Pin > Pout eff. More common is around 94% or less so using the PSU itself to set the voltage sent to the strings of chips saves several percent power eff per-board vs using 2 stages eg AC > 12V > hash board voltage regulators > chip strings.
Another bonus is that using more chips in each string allowing the higher voltages reduces the voltage differences that can appear across each chip in the string making it easier for tuning to find a stable operating voltage.