Obviously you totally have a point. We have no concept of precision. The problem is we are secondary users of data collected during healthcare, and therefore no influence over its generation. We are just passing on the data from the EHR or other sources and ETLing them into the OMOP CDM. The “poor ETL schmock” (as they are sometimes compassionately called) has no way of fixing this, even if we introduced some mechanism. So, it is up to the analyst or analysis tool to make assumptions.
The good news is that precision in medicine is generally low. Data are crude. There is no meaningful difference between 6.4 and 6.41 lbs. And all users of the data make assumptions about this low precision when they do their work.
The date situation is different, though. We do need to think of how to handle this better, because our standard resolution is one day, and today we cannot go lower (we can go higher with datetime). There is a discussion already under way. Please join.