You can figure out actual PPM of each element with the information on the bottle. The conversion only applies to meters. They measure EC and then convert it to PPM, but the problem is the ingredients all have different potential EC and the different conversions make it confusing to compare one result with another.
EC is an actual measurement. Although you can't get actual PPM from it. PPM is also a real unit of measurement, but it can't be calculated very accurately by a meter. When you are using a meter you have an actual EC measurement or a guess for PPM based on one of three equations.
So while neither EC or PPM measured with a meter tell you exactly what is going on. EC is less likely to be misunderstood.
Anyway the short version is you can figure out actual PPM. You just can't measure it with a meter.