The FCC's June 2016 conclusion to their request for comments on the ARRL's proposal (RM number 11708) was; They agree that a hard baud limit is not good, but the bandwidth limit proposed by ARRL isn't any better, so FCC denied the request.
Theodore Rappaport, N9NB has been making a fairly big media campaign to get the FCC to dismiss the the subsequent pending Notice of Proposed Rule Making (Docket No. 16-239). His issue is that wide-band connected digital modes and modes that are hard, expensive (or need proprietary hardware, firmware or software) to intercept communications on-the-air need to be removed from the amateur bands.
He goes so far to say that these these modes encourage crime, terrorism and are a threat to national security.
I agree with his first part, but won't go that far out on a limb to make his secondary claims. Having open communications in ham radio is essential to preventing unauthorized use of the bands/self-policing. It's also essential to the self-learning/training aspects of the hobby. Anything else stifles innovation
Ham radio operators have long been some of the original open source , Do-It-Yourself (DIY) proponents. I wrote about this some time back after the economy collapsed.
Bruce Peren's K6BP brought this proprietary "black-box" problem to the forefront back in 2006. At that time he was concerned about the proprietary vocoder in D-Star.
In a reply RM-11625 comment from Bruce Perens in 2012, he made the suggestion that comment that only open source protocols be allowed...
"Amend Section 97.309(a) to read:
Any digital code that is fully disclosed to the public in sufficient detail that a Knowledgeable person can create a computer program to encode and decode it, or any digital code of a type specifically authorized in this part, may be transmitted."
I'd be in favor of Bruce's suggested emission code language in conjunction with the FCC's intended resolution for removing the symbol rate and not adopting a bandwidth limit.
Many may respond that this will there would be detrimental effects from banning existing technology like Pactor and AMBE. Radio amateurs will simply have to undertake an joint effort to reverse engineer protocols and/or petition the manufacturer's to create an open specification of their technology.
APCO (the Association of Public-Safety Communications Officials) required this very thing in relation to their standard, P-25. And ham radio should also adopt that type of policy. The future of radio is more and more software defined, so sharing information/specifications and working together is what ham radio has always been about.
What is more disturbing to me is that the "leaders" of ham radio haven't really even gotten on soap box about this, let a lone proposed a solution.