Someone might have already pointed it out but for me, the sentence of RA is not the main issue, the issue is allowing a single person to stamp through an entire legal system and undermine all of the time and money that is invested in it, even if that person is a president. I suspect that the idea originally was to give some safety valve but if it is used more than a few times by a President, it makes a mockery of it…
The main failure here is the failure of the elections system to elect anyone reasonable. On its own it is not that bad an idea for someone who carries a mandate of the majority of the population to be able to grant pardons.
Honest question/thought experiment: if we only elected people who are qualified for their job (assume we can measure competence at least in some dimensions like we do for a myriad of other professions before we allow people to work in them) and if the election process was set up in a way where when casting your ballot you have to take a multiple choice quiz which tests for basic knowledge on what you will vote for and the country you’re in (as in “what is the household budget roughly, is this candidate in favour or against x, did the crime rate increase or decrease nominally” take these as rough examples of what I mean), to ensure that the people who vote for something have some clue what they are voting for and the broader context it’s embedded in (we require a license to drive a car, this would be akin to have a having a license to vote) would that remedy the situation a little? The idea would be that informed people would vote for informed people. Could you imagine this being a net benefit or not? I would assume it would make democracies significantly better than they are now. Imagine going to a doctors office to find out your doctor is a Plummer and he was voted into this job and that the people working for him and handling your prescription is a random assortment of people he seems to like.