All fields pervade all of space-time. That’s what a field is. Some of them might have zero value, or nearly zero value, in some places, but the field is still there.
If you insist on pointing to something in modern physics and saying “Look, physicists still believe in ether!”, then point to dark energy. One name for dark energy (or rather, for one relatively common model for dark energy) is “quintessence”, which literally means “fifth element”, a reference to ether (or alternately, to Mila Jovovich, who looks a lot better with her shirt off than ether does).
But the concept of “ether” has changed dramatically throughout history, with so far as I can tell the only common thread being “stuff that we don’t know much about”. By the time of Maxwell, the defining feature of “ether” was its stillness: It was the stationary reference frame that the speed of light was measured relative to. But in the original Greek notion, its defining feature was its lack of stillness: Ether was the ever-moving, which made up the stars, and accounted for their perpetual motion through the sky.
Now, if you do decide to latch onto that common historical thread and define “ether” as “that which we don’t understand very well”, then there will of course always be ether, but it won’t always be the same stuff. I’m not sure that’s a very useful definition, though.