I don't think its sudden hype, I think we realized how underutilized it is.
The issue with etomidate is that it does not provide any analgesic properties. Outside of the induction window, maintence sedation is required with analgesia. (Propofol/fentanyl, midazolam/fentanyl, etc) For most EMS providers that use etomidate, they are usually at the hospital before this is an issue, or have some type of maintenence sedation protocol. Serial doses of etomidate are not an option. They learned that lesson the hard way in burn units.
Ketamine provides both anesthesia, and profound analgesia. It's not a wonder drug by any means, but this it does well.
For chemical restraint, I wouldn't say that one drug is superior over the other. However, there are benefits of inducing a complete disassociative state, although doses as high as 5mg/kg IM may be needed.
Basically, if you want to knock them on their a$$ instead of just taking the edge off, ketamine is the drug. I don't see many anti-psychotics used in EMS.