Why Britain wasn't ruled by an Emperor?

As many of you would know, Britain was an Empire, that ruled wast swaths of land, at its peak, it ruled 1/4th of the world. Despite this, British monarchs simply used the title of King and Queen, but the title of Emperor outranks these titles. So, why Britain was not ruled by an Emperor?

When the title of Emperor gets adopted, it usually happens after huge political changes. For example, France becomes an Empire after the French Revolution and the failure of the Republic, and Brazil becomes an empire after the declaration of independence from Portugal. Apart from that, it could also happen after a country claims to be a continuation of an old empire, for example, Russia claimed to be a continuation of Rome, after falling of Constantinople, and claimed to be an Empire, or 'Tsardom'. In case of Britain, there was none of those, so there was no pretext to claim the title of Emperor.

Another reason British monarchs didn't adopt the title of Emperor is, Emperor's literal meaning is 'king of kings'. The United Kingdom was a political union between England, Scotland, and Ireland and this union was on paper a nation of equals, and the British monarch was king of all of them, so there was not another king in the British Isles, therefore British Monarchs did not need to outrank another king. Also, Britain had a strong parliamentary tradition, especially after the revolution of 1688, monarch's powers were limited. But the title of Emperor means king of kings, so it could be interpreted as an absolute monarch title, which was a no-no by the parliament.

But in the 1870s, there was an attempt by Queen Victoria to take the title of 'Empress'. At that point, there were a lot of Empires in Europe, that were also relatives of the Queen, and she did not want to be outranked by them. But at that point, Britain was going on a democratic path, so any title that symbolizes absolutism was not acceptable. So, British Prime Minister Benjamin Disraeli came up with a solution. He suggested that British Monarchs can take the title of 'Emperor/Empress of India'. India has many semi-independent kingdoms, so the title can preserve the meaning that it meant 'king of kings'. Also, at that time Indians were not equal to Europeans in the eyes of Britain, so absolute rule over them was fine.

This offer was accepted and Queen Victoria soon took the title of 'Empress of India'. Therefore, British Empire did not have an Emperor/Empress, but one part of it, India, did.