It is obligatory to emigrate if the country you live in does not allow you to freely practice your religion, i.e. to perform your ritual duties such as prayer, fasting, paying Zakat and observing dress code etc. The Quranic verse and the Hadith you quoted is referring to Muslims who continued to live in Mecca after the emigration to Medinah and didn't practice Islam and infact participated in the battle of Badr against the Muslims(Ibn Kathir).
As far as I know, the laws in the UK do not contravene religious freedom and infact are extremely accommodating. In that case it is permissible for you to continue living there.
Once a bedouin came to the Prophet (ﷺ) and asked him about the
migration. The Prophet (ﷺ) said, "Mercy of Allah be on you! The
migration is a quite difficult matter. Have you got some camels?" He
replied in the affirmative. Then the Prophet (ﷺ) said, "Do you give
their Zakat?" He replied in the affirmative. The Prophet said, "Do you
let others benefit by their milk gratis?" He replied in the
affirmative. Then the Prophet asked, "Do you milk them on their
watering days and give their milk to the poor and needy?" He replied
in the affirmative. The Prophet, said, "Go on doing like this from
beyond the seas, and there is no doubt that Allah will not overlook
any of your good deeds." [Saheeh Bukhari 63/149]
Narrated Malik: We came to the Prophet (ﷺ) and we were young men
nearly of equal ages and we stayed with him for twenty nights. Allah's
Messenger (ﷺ) was a very kind man and when he realized our longing for
our families, he asked us about those whom we had left behind. When we
informed him, he said, "Go back to your families and stay with them
and teach them (religion) and order them (to do good deeds). The
Prophet (ﷺ) mentioned things some of which I remembered and some I did
not. Then he said, "Pray as you have seen me praying, and when it is
the time of prayer, one of you should pronounce the call (Adhan) for
the prayer and the eldest of you should lead the prayer. " [Saheeh
Allah's Messenger (ﷺ) said, "There is no Hijra after the Conquest (of Mecca), but Jihad and good
intention remain; and if you are called (by the Muslim ruler) for
fighting, go forth immediately. [Saheeh Bukhari 56/2 ]
In the absence of compulsion and oppression in religion, it is still a Mustahab(recommended and virtuous) act to live in a Muslim ruled land, and to emigrate to one ... but it is not sinful if you don't do it, since not doing a mustahab act is not a sin.
Quote from the Imam Nawawi's Minhaj al Talibin:
The law recommends a Moslem inhabiting an infidel country to emigrate,
even though he may enjoy there the free exercise of his religion ; and
this émigration becomes obligatory if he is deprived of the exercise
of his religion, and he possesses the means enabling him to emigrate.
The above view is shared by the Shafi, Hanafi and Hanbali schools of thought. Malik and many scholars of his school differ about it (consider Migration as always obligatory.)