I agree with youTime will show but I don't think the song will be very successful. His single 'Daydream' also made 10 mil+ views on the first day of releasing but now it's been over a year and the song is at like 100 mil, which is nothing compared to the first day. I mean bts hype is just in the beggining and then it slowly dies (because fans are streaming like crazy..it's not even the real number of people viewing the song because 100 000 army dummies may be streaming it 10000 times so... that's why many times Youtube is deleting views, but they will never officially confirm why, because army has the power to kill the entire platform/website
Things will definitly change for bts from now on. May be there still isn't a group distinguished enough to steal people's heart like bts. But once it appears bts career will be over. I mean it happened with bigbang which was considered the best of the best so it can happen with anyone!!!
But the fans alone are able to pull very high numbers and from the numbers alone their decline seems far(they keep increasing)
I agree the hype around them is less, west is not used to so many releases every few months, and i think that's why they are collaborating with so many artists, to try to keep the interest at least with the western artists.
I want to say that in my opinion before they will decline there will be a substitute, there will be a new group that will pull close numbers, that's the way it always happened, BeeteeEs too after all filled a void after very big groups disbanded or went hiatus for military.