It may have been designed that way. In other words,
it is 'softer' than the flywheel gears, so that it
goes first, and is easier, (and cheaper), to replace.
However, they may have gone too far with that.
You may find an aftermarket replacement that is better
built. Most automotive aftermarket parts, nowdays,
are sold as good, better, and best. I had a Ford
Bronco that went through a starter solenoid every
year. I quit buying O.E.M. and went for the best
and never had another problem. Of course you are
going to pay top dollar for 'the best'.