If there is true meritocracy - those with the most talent rise to the top - then statistically you should see a fairly even sampling of demographics in any given occupation. That is, there should be approximately 50% of CEOs who are female, and the racial make-up should roughly equal the demographics of the US. Now, there may be some skew in gender in high time demand occupations due to traditional gender roles and some women choosing to put family over career, but the current skew is too much to explain that. You cannot point to individual success stories as a counterpoint. When you have large enough numbers a few will always slip through but the overall point remains - a point made well by a quote that shows up a lot in Quality Improvement: “Every system is perfectly designed to get the results it gets.” US education, finance, healthcare, and business systems are designed to put white males ahead. The point always seized on by conservatives to argue for the status quo is to claim liberals want equality of outcome (I.e. communism). This is not accurate for most. Equality of outcome is not something the government should try to enforce. However, what liberals want, and do want the government to strive for, is equality of opportunity - the American Dream.
It’s an impossible goal to fully reach and as you note there will always be factors such as the death of a parent that will disadvantage some people. However, there are thousands of small problems with the status quo that all act together to push poor people down and lift rich people up. Poor quality inner city schools, the War on Drugs (harsher sentences for crack vs regular cocaine, lifelong ban on financial aid for those convicted, creation of many single-parent households), implicit bias (equally qualified minorities and women less likely to be chosen for a job, security guards following people of color around a store), criminal justice system bias and misconduct (militarized police in poor areas, harsher sentences for minorities for the same crimes, Driving While Black), the US healthcare system (poor preventative care for those in poverty, parents forced to choose between insulin for their diabetic kid and making rent), food deserts...
The tools often proposed to deal with some of these factors are imperfect instruments, but largely amount to transfer of wealth from the rich to the poor via taxation, in order to provide the poor with some small measure of opportunity. The rich, and the politicians they have purchased, argue vehemently against that and want you to believe it is injustice - discrimination against the victimized, vilified white male.