This is exactly a situation where having the information benefits you. You think you are playing perfectly and without error, and without that information you would continue to play the same way until you hit a wall, such a savage fight, and then be frustrated without a clear direction for what the issue is. This may not describe you specifically, but there are players where you are at currently who do have those goals in mind. With the data, you can take that parse through xiv analysis and see what you are missing. For example, here is a fight where you have 0 deaths.
https://xivanalysis.com/fflogs/aN8zmyvg6BR4DF1C/1/6 I make no judgements, but it does give some suggestions for areas of opportunity and growth that appear to be consistent across many of the other fights you have participated in. Perhaps you are a person who only does normal trials/raids and has no aspirations for anything more difficult - this information is likely not as relevant outside self-improvement.
If you are skeptical, you could try comparing your battle log to what is being reported (although tedious).