You can replace a roller yourself if the door is down, the springs aren't under load, and you're only swapping the bottom rollers, which don't carry cable tension. That's a screwdriver-and-pliers job for most people.
Where it stops being a DIY job is the top rollers, because those sit inside the track section right where the cable and drum are, and the door is still under spring tension even when it's closed. Pull the wrong bracket there and the door can drop or the cable can jump the drum, which is a hand-injury risk, not a inconvenience.
The honest limitation: if more than two or three rollers on one side are worn, or the track itself is bent where the rollers ride, swapping rollers alone won't fix the shudder - the track needs straightening or replacing first, and that's not a bracket-and-screwdriver job.