The radio delay makes any kind of direct control impossible. All Mars landers have had to handle landings on their own.

Space probes exploring other planets or the rim of the solar system have the same problem, usually worse, but they don't often have situations requiring split-second decisions. A probe around Saturn can report any problems at its leisure, and wait for the fix.

An idea appealing to some of the more cautious Mars exploration types is to begin manned exploration of Mars with an Earth-supplied space station in orbit around Mars, or based on one of the moons. Scientists would then be close enough for direct control of squads of remote rovers, flyers, sample returners, and all the rest.