Blame for tough gamey caribou rests squarely on the hands that handle it. It's a sorry state of affairs any time folks blame the animal for their own sloppy ways.
Handle it right, and caribou is good enough you'll be rationing it out of the freezer before it's gone.
Don't go rubbing your hands on the hair and hide, then handling the meat. One hand for the knife and meat, and the other for the hide. Carry some of those little hand wipe packets and use them to clean your hands thoroughly before packing up the meat for carry.
If it will be a few days before your pickup plane arrives, you are going to want to hang the meat in fabric elk or moose bags so it can air and drain. Forget about the "deer bags" made of cheese cloth, cuzz they don't turn flies or dirt. If you can't manage to hang the meat, lay out your bags of meat on a tarp overnight so it can air, then be sure to shade the meat on sunny days.
Hunting strategy varies hugely with the location and time of the year. Later in the fall as cold weather approaches, yeah, they're going to herd up and start to move. It's an impressive sight to watch the herds and it will sorely test your fitness trying to intercept those fast movers.
But until the weather cools and the herds form and start to migrate, they are scattered. You'll see small herds of cows and calves, but the bigger bulls are pretty solitary. I don't recall ever seeing more than a handful of bulls in a bunch before migration, and more likely you are only going to see one or two at a time.
Whether early or late, bring along a good spotting scope, binoculars and heck of a set of legs and lungs. You'll be surveying large tracts of land, then moving out to connect.
If the migration has started, don't panic too bad if you can't get in front of a herd. Mark their travel route and stake it out for the next batch to come along. There are natural "funnels" in lots of places that herds will pass through, and that's often where smaller herds meet up to make bigger herds.
Get in shape now, and do a good job of it. Poor conditioning ruins more caribou hunts than anything I know.
