FWIW, I do not oppose them. Some catholics oppose them, others do not. It is not a monolithic political position. Improper generalizations should be avoided.
Pretty much in any group, the most vocal and activist tend to be liberals. That doesn't mean that all in that group think and feel the same. There were Catholic nuns who supported the Sandinista’s in Nicaragua, but most Catholics didn't (at least to my knowledge), because they recognized that the Sandinista’s were essentially Communists.
As an aside, the Sandinista’s supported ‘democratic socialism’, same as Ocasio-Cortez and Sanders.