I have read both of these two good questions and answers and I got the answer of my question, that in the modern English "it" is used more than "her" while referring to a ship or country.
- Using 'her' vs. 'its' to refer to a country
- Is it a good practice to refer to countries, ships etc using the feminine form?
My question is not to use which of "she" or "it", but my question is why in the past "she" had been more prevalent than "he", specifically when you read history, you see that the people (of English-speaking countries) in the past had been more "masculinist" than now?