Toyota sell both complet FDS (AKA CV) and half shaft. The half shaft are comprised of all but inner CV tulip (races, bearings and axle). Unlike some parts, that are only manufactures during vehicle production. FDS, are being manufactured today.
Main reasons for failure of FDS:
Loss of CV grease. (hole in boot or lose clamp)
Contamination in CV grease. (hole in boot or lose clamp).
Loose wheel bearings, resulting in FDS vibration. (reduces life of CV bearings, races and axle splines)
Loose wheel bearings and excessive hub flange snap ring gap. (Results in, outer axle splines being eaten.
Reuse of hub flange snap ring. Result in rounding & enlarging of outer axle groove for snap ring. (snap ring no longer can be retained on axle)
Bouncing off rocks, under-power. (Snapping axle, cage or cracking tulip.)
Re-booting is viable, if: FDS has good splines, and both CV have zero play (Races and ball bearing in perfect condition). Except life, if perfectly care for IMHO ~250K miles, more if all HWY miles.
Another reason to use only OEM FDS, not often considered. Outer axle seal! This seal mates to knuckles rear seal. For these seals to work. They must be pulled tight (hub flange snap ring gap of less than 0.20mm) into each other and mate perfectly. A failure of these seal, result in axle needle bearing grease contamination. This contamination can make it's way into wheel bearings.