You never know, one day Vpop will have a group like BTS that is super popular. I remember when BTS were rookies and no one really talked about them. They were doing gigs with other artists in different countries including Vietnamese artists.
If you look at Kpop, there are also so many rookie groups that debut and failed. I think it only looks like Vpop groups fail because we don't really debut that many groups as Kpop does. I can only name about 5 groups in Vpop history. Kpop has tons of groups that debut and vanished. Like hundreds.
I'm crossing my finger that one day there will be a group that is very popular in Vietnam, even better if they get popular in the US.