I wonder whether material science has advanced enough that new probes could be landed that last for longer. I mean the pressure isn't as high as the bottom of the Mariana Trench. Or a balloon that hangs about in tolerable pressures / temperatures.

It's a combination of pressure (93 bar), temperature (900 F / 475 C), and the local chemistry. And then there's the trace amounts of hydrogen fluoride, hydrogen chloride, hydrogen sulfide, and sulfuric acid.