He is asking about the worst of people and the worst in disbelief: is it Pharaoh or Abu Lahab?

Focusing on such matters and arguing about them is a waste of
the Muslim’s time and energy, that he could have spent on things that are
more beneficial to him and to the Muslims around him.

The Muslim needs to know the most perfect of people in faith
and the best of them in attitude so that he can follow their example and do
deeds like theirs, more than he needs to know the worst of people in
disbelief.

So long as it is established in the Muslim’s mind that the
two people mentioned were disbelievers in Allah and enemies to Him, for
Allah warned them in His Book of the most severe punishment, that is
sufficient.

But if the Muslim’s aim in finding out about these people is
so that he will be more cautious of doing deeds like theirs and so that he
can warn people about such deeds, then there is nothing wrong with that.

Secondly:

If we look at these two men and their words and deeds, and
what was revealed concerning them of verses in the Holy Qur’an, we will have
no doubt that Pharaoh was worse in terms of disbelief and stubbornness than
Abu Lahab, because he claimed lordship and divinity, and he called the
people to sanctify him and venerate him, and he thought little of his people
and they obeyed him; he misled his troops and they supported him; he showed
enmity towards the close friends of Allah and tortured the people,
slaughtering their sons and letting their womenfolk live. No arrogant tyrant
is mentioned in the Qur’an as much as this tyrant is mentioned. Mention is
made of his abhorrent words and deeds, and of his wrongdoing, stubbornness
and tyranny, and of how he misled his people and led them astray. And
mention is made of his terrible fate on the Day of Resurrection. Allah, may
He be exalted, says (interpretation of the meaning):
“The
Fire; they are exposed to it, morning and afternoon, and on the Day when the
Hour will be established (it will be said to the angels): ‘Cause Fir‘aun’s
(Pharaoh) people to enter the severest torment!’”
[Ghaafir 40:46].

As for Abu Lahab, he disbelieved in Allah and His Messenger,
and took people as enemies or as allies on that basis, and he died in a
state of disbelief and loss, but he did not cause as much harm to the
believers as Pharaoh did, and he did not go as far in disbelief as Pharaoh
did, who claimed lordship and divinity, and said:
“ ‘I am your lord, most high’” [an-Naazi
‘aat 79:24] and
“ ‘I know not that you have an
ilah (a god) other than me’” [al-Qasas 28:38].

Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him)
said:

It is well established among the people of all religions,
Muslims, Jews and Christians, that Pharaoh was one of the worst disbelievers
in Allah; in fact in the Qur’an, Allah does not tell the story of any
disbeliever by name more than the story of Pharaoh, and He does not tell us
more detail of the disbelief, transgression and arrogance of any disbeliever
more than He tells us about Pharaoh. End quote.

Majmoo‘ al-Fataawa
(2/125)

And Allah knows best.