This would imply Disney is driven by guest satisfaction and not bottom line dollars, which we know is backwards. I don't see magicbands going away until Disney decides they cost too much and aren't worth the marginal improvement to guest satisfaction that they offer.
Besides, magicbands are actually quite nice and do improve the guest experience. To be clear -- NO -- they were not worth the massive investment Disney has made in MyMagic+ instead of attractions, but they are convenient, especially if staying on property. I don't really see anything negative about the bands themselves and those who don't want them can still get RFID cards instead. They weren't worth the investment, probably, but that investment already happened. Give them a try, you'll find they are actually kinda nice.
Everyone -- this board and Disney's Board -- needs to move on from MyMagic+ and accept that it will never deliver a ROI, but instead was a sunk cost to offer marginal improvement to the guest experience. Ironically, in some ways, it's one of the most Disney things Disney has done in a while (albeit, completely unintentionally). Instead of waiting for an ROI that will never materialize, it's time write it off and move on to investing in the parks the old fashioned way -- building attractions.
ETA: although, now as I reread your post, perhaps you post meant they aren't getting people to come back, which I would agree -- they won't do that. Not, as I read it at first, that they aren't coming back because of them. In short, magicbands won't change guest behavior one way or the other, IMO. They are nice, but not influential.