There may be a grain of truth in what you are suggesting here but as is also true with statistics, numerology can be at times abused to support any current theories about the nature of reality, often based upon very shaky assumptions.
That is however the situation when numerology is abused or misused.
When it is used properly in combination with other intuitive and non intuitive/logical information with no preconceived theories or ideas about what the explorer will find, then it can become a valuable tool for better understanding the forces which are acting upon us throughout our lives.
The type of superhero to which you are referring is completely fictional, whereas all of us have the potential to become real superheroes in the eyes of the people whom we care about, whatever year or century and numerology reduction it is at the time.
What does your theory mean for new fictional superheroes in the 21st century, where 20 reduces to 2? And what does it mean for 20th century fictional superheroes who have survived long enough to see the 21st century?
The number one can mean new beginnings, but it can also mean creation, independence, uniqueness, motivation, striving forward and progress, ambition and will power and positiveness. Number 1 also resonates with the energies of pioneering, raw energy, force, activity, self-leadership and assertiveness, initiative, instinct and intuition.
Your interpretation completely and conveniently ignores everything else on this list.
Therefore so called "cherry picking" or selecting one characteristic associated with a particular number and ignoring any alternative tendency can in the wrong hands grossly distort and mislead someone into believing something which is only at the best a very small part of the truth, or at worst make them believe something which is not true at all.