I was hopeful when I heard about mainstream loudness normalisation. I've been using ReplayGain for years and it's still superior due to storing both track and album level. It's unclear to me what Spotify etc is doing, but it's is track normalisation it's going to ruin albums.

There's a bigger problem, though. My girlfriend complained about volume fluctuations in her car between tracks. She uses an iPhone so I enabled "Soundcheck" (Apple's normalisation). It works fine in the car. But now she complains that headphones simply aren't loud enough. It turns out that the volume controls are essentially made for overly-compressed, loud content and can't sufficiently amplify dynamic content.

So, unfortunately, people will just turn it off and there's still an advantage to mastering "loud".