I totally agree with you friend @knowledgefruit when it comes to human potential comparisons are never good, in addition to all the factors you expose, there is even the issue of time. At some point someone may feel better or more "successful" than another, however after a few years this situation can be completely reversed, so the previous analysis (very limited by the way) would only apply for a certain amount of time.

Not to mention that the concepts of "better life" for some could only refer to "greater amount of accumulated goods", while for others it represents, for example, greater freedom or greater happiness ... how to compare or measure success comparing both ?

The best thing, as you say, is to observe ourselves, try to determine if what we have achieved or what we have achieved satisfies ourselves, our success therefore will not depend on how well we have done with respect to others, but how satisfied we are with ourselves.