Since 1975 the communist government has not opposed Buddhism but rather has attempted to manipulate it to support political goals, and with some success. Just like the other Commie gov in the world they manipulate the religion to meet their state beliefs.
LOL. Ever been to Laos? Ever talk to any Monks there? Ever attend any religious ceremonies there? I have. The government has used religion to further some of their own goals, but has in no way prohibited religion from being freely practiced.
Of course everything is not perfect, far from it. For example, there are two sets of donation boxes at Temples. The 'main' donation box, which most foreigners will donate into, is collected and kept by the government. The smaller box, usually off to the side, is kept by the Monks and used by them. It is a hindrance, but they in no way prevent the monks, or common people, from going about their worshiping. It is a far cry from your statement about communist nations never allowing any religious worship.