I may be wrong here but ...
I believe Bravo's a canadian station - (thus the pro-gay reputation[?]) a part of the CITY-TV family of stations.
Bravo is part of the NBC Universal family in the USA. Often, however, country-specific versions of the network are developed for distribution abroad. These often are partnerships with other entities. In Canada, Bravo partners with CTV-Globemedia. In the UK, they are associated with Virgin and the entire focus of the network there is on male viewers (they even have a completely different logo).
No basic cable networks HAVE to censor - the FCC does not regulate content of basic cable networks. However the cable industry maintains voluntary compliance with the rules that govern over the air broadcast television, with a bit looser conduct when it comes to profanity. Different networks have different standards.
Bravo, which has more gay-themed programming than any other non-gay oriented cable network, opened themselves up for this backlash by someone's overeager cutting and dubbing. Most people actually prefer you just go silent during expletives instead of the clumsy dubbing work (Scarface's dubbed for television version was the funniest thing I'd ever seen). Bad dubbing is always distracting. My guess is a Hollywood based distributor was actually responsible for the hack job. They usually are the ones to market a "broadcast ready" version of a movie, and the network just runs what they get. But an exclusive cable run does give extra power to Bravo to request changes to the cutting and pasting the distributor does, which is why they are claiming they'll do better next time. Chances are, Bravo will rerun the movie many times before their contractual window ends. After that, Brokeback Mountain will become available to broadcast television, and THAT will be real interesting when a network decides to run it for the first time, probably during one of those summer "Movie of the Week" events.