https://en.wikipedia.org/wiki/Competition_and_Markets_Author...
https://en.wikipedia.org/wiki/Competition_and_Markets_Author...
From wikipedia:
Type Non-ministerial government department
"A non-ministerial department (NMD) is a government department in its own right, but does not have its own minister. However, it is accountable to Parliament through its sponsoring ministers."
> https://www.gov.uk/guidance/public-bodies-reform
UK ministers (politicians) can absolutely influence the CMA, there is no vote on its leaders - they are simply appointed by the Business Secretary, who can pick whomever they find most favorable to their own objectives. The Business Secretary can be replaced at any time without a vote by the Prime Minister too in a reshuffle.
The only real check on the CMA would be the UK's judicial review process, if a decision was especially egregious.
> In the UK, the term quango covers different "arm's-length" government bodies, including [...] non-ministerial government departments
https://en.wikipedia.org/wiki/Quango
> The Competition and Markets Authority [...] is a non-ministerial government department
https://en.wikipedia.org/wiki/Competition_and_Markets_Author...
But this specifics of what is and is not a quango don't matter. The original claim implied that the decision was made by a politician for political reasons and this isn't the case.