It was politicized as soon as their QB and coach decided to openly endorse white supremacy.
Sorry if the real-life suffering caused by their president bleeds into your entertainment.
Tom Brady and Bill Belichick are just two people of an organization consisting of hundreds of people. Granted, they are two key people but you still can't make the case that those two people outweigh all the other players and coaches that might be on the opposite side of the political spectrum.
Also, it is not like Bill Belichick and Tom Brady officially declared to play and win for President Trump. If Brady took the Lombardi Trophy from Terry Bradshaw while screaming 'This one's for President Trump! MAGA!' I would understand the politicization. But I don't think that politics was even on the mind of any of the players or coaches in that moment.
Certainly Trump and his allies will try to capitalize on the Patriots' win even if just by associating themselves with them (e.g. inviting the Patriots to the White House, shooting some nice pictures). Every president does that. But they can only capitalize on it if the other side accepts this politicization to happen by accepting the ridiculous assumption that just because one player and one coach more or less publicly admitted their support for Trump (or at least didn't deny) this makes it a win for Trump.
Robert Kraft was one of the biggest donors of President Obama in 2008 and 2012. Who in their right mind would have claimed that the SB win two years ago was a victory for Obama???