I don't think most proponents of paper targets view them as either perfect or a panacea. However, for me there needs to be an absolutely clear advantage to any new system in order to justify making a change that will affect every single participant. I don't believe that new is necessarily better, or in making changes simply because we can. I'm personally just not seeing such a clear advantage at this point for E-targets. Certainly they can shorten the length of matches, but I've never viewed that as an advantage. I anticipate devoting the better part of a day (or weekend, or week for a big match) to a match and don't see a real benefit to completing a match in 3 hours. Like you, I do view the information return from E-targets as one of the big benefits to their use. That is information that was not readily available previously to competitors and can be very useful toward improving your shooting if analyzed and used properly. However, that is data I can also generate myself during practice sessions, so it's not like I wouldn't have it otherwise. I am not particularly concerned with any scoring "accuracy" issues with E-targets, the accuracy is what it is. Any such issues will only improve over time as the systems develop further. The "missed shot" and/or "taking an extra shot" issues are a little more troubling, but as the technology is developed further and users gain more familiarity with their systems, I'm sure those issues will also largely be resolved.
Call me a dinosaur, but I guess for me it boils down to the changes in how you shoot a match and being forced to look at a tablet and shoot on E-targets or else not participate. I've never particularly cared for having things I don't want forced down my throat without any input and then been told, "It's the way of the future, so get over it, or else don't show up". I don't treat others that way and tend to dig in my heels when it's done to me. There really is no in-between because ranges that have adopted them are probably never going to revert to paper targets. Unlike individual decisions made about one's personal shooting equipment, a decision to switch to an E-target system will necessarily impact every shooter that would like to participate. There's really no way to do both. More often than not, such decisions are made by one person (or a very small number of people) fairly high up the food chain. As far as their adoption locally, I'm relatively safe for the time being because my home range just completely re-worked our 600 yd range and pits with traditional target carriers. After the cost involved in that project, I don't envision the powers that be adopting E-targets anytime soon, not that I would have any real say in the matter if they did.
There are several ranges in my area of the country that do use E-targets and I simply have no real desire to go through the effort of preparation and travel time/expense and compete because of that. I don't harass my fellow competitors that favor their use for having a different opinion than mine, but I personally don't have much interest in participating. As I've stated on numerous occasions, I have no doubt that E-targets are the future of the sport. I'll participate when and where I can at venues that still use paper targets, but at some point I'll probably be forced to either accept their use or hang it up. I guess that's the way of all dinosaurs...you either adapt or go extinct.