Taxis have democratic support because they are unionized, Uber, Lyft et all. have Republican support because they're not. The air industry is government subsidized and unionized but Republicans like them because they are a big link in to oil and military. Greyhound... Wait, it's still around? The company is not subsidized and always on the verge of bankruptcy. I'm surprised Republicans don't rally behind them.. maybe it's because the people who ride these buses are just too damn poor to care about politics at all.
California has had a decade of political war over the bullet train from SoCal to NorCal. Republicans are adamantly opposed while Dems are heavily in favor. Airlines and car manufacturers are financing/supporting opposition (yes, including Musk), rail unions and California dems are in favor.
My take is that rural California is Republican and a bullet train line would quickly increase urbanization of towns now considered too far to commute from, like Fresno or Bakersfield. Demographically, urban centers generally vote Democrat and the fear from rural Republicans is not only loss of agricultural land, but loss of elections on top of a Democrat voting union labor running the rail line.
Competition among large corporations in American is closely tied to political support and vice versa. Many will support both parties out of an abundance of caution while some go out of their way to show their support for one or the other (like the gun lobby or the union lobbies). It's just how America works, unlike in Europe where the connection is far more subtle. We elect political representatives who then go on to act on behalf of the lobbies who financed their election... No wonder Americans are so cynical about politics in general!