For those curious, this hypothetical mission would take longer to get to Pluto than New Horizons because it wouldn't just be flying by, it would need time to set up a slower approach and enter into orbit around Pluto and give the lander time to collect the sample.

It would also need enough fuel to then change trajectories and return to Earth, as well as all of the fuel for the lander. These types of sample return missions are very expensive, which is why there have not been many. There were a few somewhat famous ones to the moon in the 60s and 70s, one that collected solar wind particles (barely had to leave the Earth's neighborhood, no landing required), one that flew through the tail of a comet and collected dust (no landing required), and one by JAXA that retrieved a sample from an asteroid. It's ultimately cheaper to bring the science/instrumentation to the object than the other way around, and those are the types of missions that get funding.

A rover is far more likely than a sample return mission, but even so I wouldn't put money on a return to Pluto in the very near future.