The 7.5% growth follows the "9.4% fall in GDP in 2020, when Covid-19 drove the economy into a steep slump". Source: The Guardian.

There is a Wikipedia article, where the influence of economic aspects of Brexit are outlined.

One of the most dangerous issues in the long term is the realistic possibility of either England being left on its own, or with Wales, when there would be no Britain left to speak of. That could happen if Scotland would at some point vote for independence in order to be able to rejoin EU, while the rising support for Sinn Féin could result in Northern Ireland becoming a part of Ireland. This latter prospect could potentially become a particularly tumultuous affair. And all that because of the fact that no matter how the majority in NI and Scotland vote in general elections or referendums like one on Brexit, England sets the tone.