I agree, but some people also like that kind of thing to prove how far they got in a challenging game. So for that I think some retro games would really benefit from that kind of achievement. Like the famously difficult games such as Ninja Gaiden, Battletoads, etc.

Also, some of these "pointless" achievements can be used as a negative proof. For example, the lack of a "weapon used" achievement with the presence of a "last boss defeated" achievement proves you beat the game without using that weapon. This allows players to contrive challenges not foreseen by the explicit implementation of an achievement.

Now, one issue is that on basically every platform, achievements are tracked per ownership of the game, so you can't scope down the achievements like that unless you only ever play the game with that challenge in mind. But in RA specifically, whose accounts are not tied to ownership, you could potentially make an account just to track a specific challenge, and have a public record of _your_ achievement.