I feel like the whole "cut a rope with an arrow" thing is something that shows up pretty frequently in media. Enough so that I think it's one of those tropes that can be waved away as "rule of cool." I'm not gonna knock Larian for putting it in.
I'm kinda the same way. I just accept it as part of the fantasy.
I think the first time I saw it was probably in Robin Hood.
The problem isn't that you can shoot ropes. The problem is they made everyone Robin Hood.
100% hit rate and 1hp? Why suddenly ignore the rules completely? Is it cool playing Archie the Archer when Bob the Tank with 8 Dex can take the same shot with 100% success rate, with whatever they can throw? Or would it be cooler if those kinds of shots would be something that an actual archer could bring to the party, with their high dex and Archery Fighting Style?
These Robin Hood shots could even be a great use for True Strike if you only have one chance to time it right. But no, 100% hit rate for everyone always, rope has 1hp and always breaks, no questions asked.