I suspect you're going to get a sizable number of disagreements about solo hiking (I'm just going to be first in the line.
While I agree that solo hiking requires a different response to the risk assessment, I don't agree that solo hiking is highly unsafe. You have to think more about what can go wrong, and plan your gear and contingency plans accordingly to reduce your risk to a manageable level, but hiking solo is still probably safer than the drive to the trailhead. In my own case, I tend to avoid solo hikes that involve significant off-trail travel (it's something I don't have extensive experience with, and it makes it harder for SAR to find me, should it come to that.) Other than that precaution, the only thing I do is leave a more detailed route description with my wife, and I don't change my route once I'm out there - again, making it easier for SAR if I do become incapacitated. I also make darned sure that I get out when I say I will, and immediately call my wife to let her know I'm out.
But, on the trail, I don't believe it's any less safe to go solo. I've done it many times, and intend to in the future. I don't recommend it for first-trip beginners - but I don't think it should be prohibited, either.
I strongly agree with you that a map and compass are essential - and not just for solo travel. Every group (and I'd argue that every person in a group) needs a map and compass. Electronics can fail - usually at the worst possible time (and shortly thereafter, it begins to rain.) And, it's not enough to have them: you need to know how to use them.