I’m guessing the issue is an expectation that polls should be providing data where scale is “critically important”. For example, if I was working with money the difference between 33% and 32.6843% could be very important.
What the polls feature should round to has been discussed here often. AFAIK, it is an intentional design decision that the results are somewhat “rough”, and that the current implementation is good enough for typical use in a forum.
Because a forum is meant to be a place for discussion and not data collection I agree with the decision and think that if more exact data is needed something other than the poll feature should be used.
That said, if the rounding is grossly incorrect then that is something that should be looked into. i.e. if there are only 3 votes there is no way any should have 25% instead of 33% / 66%