The USCG Auxiliary web site for Vessel Examiners has the following exchange in their FAQ section:
Question: Does the availability of electronic documentation on board satisfy the VSC requirement. Example, a vessel over 39.4 feet required to carry navigation rules. If they can be readily accessed on a computer, smart phone etc. Does that satisfy the requirement?
Answer: No it does not as a computer, phone anything electronic can break down and become inaccessible.
Note that these aren't necessarily maritime attorneys, but they do have access to the folks who enforce the rules, so they carry some weight.
I hadn't heard about any effort to reduce the length required to carry NavRules. It doesn't really make sense on a small boat. But then again, don't bet against the gov't doing things that make no sense.