Every 50 or 100 years is possibly the worst way of dealing with it. You're essentially making it a repeating Y2K / Y2038 problem.
Doing it that rarely means most people will never see it happen in their professional life, so most processes will be designed without keeping it in mind. When it does inevitably happen, everything breaks at once.
With leap seconds it happens often enough that you actively have to keep it in mind during design. Leap hours are rare enough that they'll be a society-wide event, and can probably be handled without too much issue using existing timezone logic.
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Every 50 or 100 years is possibly the worst way of dealing with it. You're essentially making it a repeating Y2K / Y2038 problem.
Doing it that rarely means most people will never see it happen in their professional life, so most processes will be designed without keeping it in mind. When it does inevitably happen, everything breaks at once.
With leap seconds it happens often enough that you actively have to keep it in mind during design. Leap hours are rare enough that they'll be a society-wide event, and can probably be handled without too much issue using existing timezone logic.