Wouldn't worry about sales too much given how ubiquitous streaming is these days. Even many diehards will not buy a copy - why would you if you are paying £10 a month for Spotify, it's all there and that's where music is nowadays. You don't need to buy an album to have the album so it's not a reflection of a drop in popularity or quality, it's just different times.

Jumping into bed with Tidal hasn't worked. They need to get in properly with Spotify- if they want a single heard, they need it on the new release playlists of the week. Same with the album, it needs to be on the new releases list to catch people browsing. At the moment, you have to go in to Bon Jovi to find the new stuff- the THNIFS re-release was just there with no fanfare at all.

Promotion is non existent outside of the states, they're not touring out of the US. They need to hope there's still a fanbase waiting for them when they do want us to buy tickets/music.