Yes and no. While it's certainly true that various weird and wonderful factors can influence the colour a particular party ends up going with, that doesn't negate the overall trend. Hence why I didn't bemoan yellow for the Labour Party - if red is already "taken" by another party, as it appears to have been here, that's fair enough. But the ubiquity of this norm does mean you need a compelling reason to diverge from it in AH, imho.Political colours are extremely arbitrary. Many parties were associated with a wide variety of colours historically, and often only really coalesced around one colour with the advent and widespread adoption of colour television.
For instance, the UK Conservative Party only officially adopted blue as its colour in 1949 (it had been using blue for a long time before then, it wasn't universally used). The Tories originally used red, white and blue, drawn from the Union Flag. Whilst the Whigs are traditionally associated with buff (a sort of tan colour), they also used blue.
Sure, whilst red = conservative and blue = liberal is a very American take, there's really no reason why a country in an ATL couldn't just have those same colour associations.
In Britain at Elections Conservative Party candidates always wear blue rosettes and Conservative posters usually feature the colour blue, so that even if someone does not stop to read the poster th...history.stackexchange.comIn this blog, Jack Tindale talks us through the differing colours of the political parties, and what the change over time represents. For all that we associate the Labour Party with red, the Conservatives with blue, and the Liberal Democrats with various shades of orange, a nationwide approach...www.policyconnect.org.uk
You could argue that the trend is merely the result of an accident of history, going from the Phrygian cap to the Jacobins to the Paris Commune to the Social Democratic movement, in which case the 1848 PoD could easily have butterflied away the Paris Commune and avoided the establishment of this international quasi-standard, but I'm not sure it's quite as arbitrary as that. (After all, many in the German Social Democratic movement, arguably the first to really popularise the red "branding" after the Paris Commune, weren't actually particularly fond of the Paris Commune, so that provenance is at least somewhat doubtful.)
If you look at psychology of colour, red is associated cross-culturally with ideas like "anger", "passion" and "excitement", while blue is associated cross-culturally with ideas like "reliability", "prudence" and "stability". At their core, progressive ideologies advocate for novelty and change, while conservative ideologies advocate for maintaining the status quo (or returning to some status quo ante.
I would therefore suggest that an overall global trend towards red=progressive (in some way, whether left or liberal) and blue=conservative (in some way, whether centrist or reactionary) would manifest in any timeline. Exceptions likewise will exist in any timeline as they do in ours - but there should be a story behind them.