As a consumer, my primary objection to streaming platforms is that you don't own any of the stuff you pay for. That's obviously different to these artists' main objection, but if the solution they propose (whether it's switching to Bandcamp or something else) also addresses that concern I could get on board with it (and will always have sympathy for artists who want a bigger cut vs the middle man).
I do still pay for Spotify despite that objection. I find it provides just enough value to justify the cost. I have found it good for discoverability and, unlike other streaming services, Spotify gives me access to pretty much any music I might like to listen to. (Others with more niche tastes might disagree.)