Politics really affects the bitcoin business, because bitcoin is quite dependent on the regulation of a country. The restriction of bitcoin by a regulation makes its price fall considerably, and vice versa, will soon rise when it gains the trust of the government.
Sadly yes, but you can can see similarity with the fiat markets, they too get a lot of movement when the political situation becomes unstable or something good or bad happens. Even they are regulated but they also face the burnt, so I think the effect evens out for both crypto and fiat markets.
I believe the only factors that's influencing Bitcoin business are just the stated point in the 1-3, 3 and 4 are actually the same thing while the change in the rules of Bitcoin (which I believe is Bitcoin protocol) is decided by the community and could only yield positive influence on the Bitcoin businesses.
Change is the rules - I can think of the SegWit debate and it was for the good only but it faced a lot of empty criticism even so much that some people, opportunistic people I say, seized the chance to start their own forks of bitcoin calling the original bitcoin as a copy cat. But then again this a rare thing happened once a decade. Halving- yes that has a temporary movement on the market.
But these things only have positive impacts on businesses. Because they are solving problems not creating them.