why did titanic save women and kids first but not in regards to covid ?

Children first makes sense. Not sure why the captain also said women first. That was his personal decision. Maybe because back then caring for kids was mainly up to women? 

Children always come first but with covid they have such a low risk of serious illness and even less of a risk of death. Its older people and people working in the healthcare that are at highest risk and needed to get vaccinated first.  

Not that I need to add fuel to the fire, but you are aware that the majority of people dying from Covid-19 are male, right?

Yet the majority of people receiving the vaccine to date (in the West, anyways) are female (because the majority of front-line care-givers are female).

Talk amongst yourselves.

It should be noted that in multiple ship sinkings before and after Titanic, there was no "women and children" first rule, or it wasn't applied, and (you'll be surprised to hear), the vast Vast VAST majority of survivors, even when the majority of people on the boat were women or children, were men.

This is a case where bigger, stronger, faster and more trained in fighting, especially when terrified, turns out to be a pretty big advantage.

That is to say, Titanic is and probably will continue to be, unusual.  It's survivor's unusual gender balance depended on the crew immediately successfully enforcing a relatively new policy which has, in most cases, since, been de-gendered.  Citing it as some sort of pattern for society is factually/statistically wrong.

Your point can better be made by showing how most cultures prefer to base their military off men and/or prevent women from becoming front-line.

It's certainly true that the vast majority of human corpses that have littered the bottom of our great oceans are male, but that is because the vast majority of sailors have been male, not because we've had (or have) a long standing policy of saving women and children over men, at least, not on the water.

First off, the women and children were supposed to be saved first *in theory* on the Titanic. The thinking behind that was that children should be saved as a priority because they're so young and have not yet lived their lives and their mothers are their primary caregivers and should be saved alongside them. However, in reality, it was carried out according to class. That's why more men from the first class cabins survived than women and children from second and third class altogether. 

Covid is something entirely different. Most covid deaths affect the elderly, people with preexisting conditions, and people in front line healthcare positions (such as nurses.) Therefore, these are the groups that get prioritized over children and younger or healtheir people that are statistically less at risk of serious illness or death. 

80 percent dying from covid are over 78.