The recent change is the fact that high-voltage semiconductors now make step-up/step-down efficient. In many cases, more efficient than purely using transformers (most semiconductor stuff still uses some form of inductive effect--they just do so at MUCH higher frequencies than in the past which allows them to use MUCH smaller components and get much higher efficiencies).

One of the big advantages of AC has to do with switching. If you flip a switch on AC, within about 10 milliseconds the voltage goes to zero as a natural consequence of the waveform irrespective of what current was flowing previously. A switch can interrupt that without much grief.

If you flip a switch on DC, it has to completely stop the current flow in the presence of a large current and/or voltage that will create a conductive plasma. That means a much larger switch for the same level of power.

There is a reason why your ISP has a huge switch and it is often encased in some inert gas. And also why it sounds like a bomb going off if it trips. And why it takes a hydraulic pump to reset.

Side note: The Pacific DC Intertie was the largest in the world until the 3 Gorges Dam interties--and it dated to the Kennedy administration and used vacuum tubes. https://en.wikipedia.org/wiki/Pacific_DC_Intertie