I've already answered this one already, - with sources, but again:
Changes over time in the number of people claiming asylum in the UK are driven in a large part by geopolitical events, since asylum seekers come mainly from countries with political and military conflicts. For example, the spike in people who came to the UK to seek asylum from 1998 to 2002 were mainly nationals of Somalia, Afghanistan, Iraq, and the former Yugoslavia, which were then sites of war
https://migrationobservatory.ox.ac.uk/resources/briefings/migration-to-the-uk-asylum//
We accepted people fleeing war in 2002, just as we have accepted Ukranians, Afghans and Syrians since 2021
This difference is those coming over in 2002 were included in the overall asylum seeker figures whereas the 2024 asylum seeker figures (the dark blue line on the graph) excludes those who have come to the UK through humanitarian route (the pink columns). If the people fleeing war in 2002 had been part of special schemes rather than just coming in through the usual asylum route, the 2002 spike would not exists.
However, there is a spike in 2021 onwards, despite the humanitarian routes being excluded and you can clearly see how much higher the 2021-2024 asylum seeker line would be if those in the pink columns were included.
Enforced returns have decreased,
Voluntary returns have decreased,
Net migration has increased with a higher proportion of non-EU immigrants making up the numbers as more EU citizens are leaving the country than are coming in
People arriving by irregular means - whether by boat or lorry has increased significantly
None of that is opinion - it is data driven fact using the governments own figures.
This issue is not 100% down to Brexit, but it certainly plays a part - the ending of freedom of movement, makes it more difficult for people to get to the UK and apply for asylum via public transport, we return fewer people, EU citizens leave the country, creating job vacancies which the British nationals are can't fill, the government allowed the backlog of claims to build up, a combination of intent and a lack of parliamentary time and money due to the cost and distraction of Brexit.
But overall, Brexit is part of the ideological drive towards using xenophobia as a way to stir up public opinion against a common cause, so that the those who are behind it can consolidate their power and feather their own nests, while everyone is distracted and arguing amongst themselves.
Meanwhile, public services go to hell and everyone but the already wealthy get poorer.