Given the cold reception that Trumpcare is receiving from conservatives throughout the country, the Bishops could easily follow their example and suffer little by coming out in opposition.

Yes.  There are some extreme conservatives that believe that the repeal does not go far enough, but they are in the minority.  Most Republicans are seeing the writing on the wall and are coming out in opposition.  They are not doing this because of any moral stance, but they see their reelection chances dimming by the hour as long as Trunpcare is the talk of the land.