I guess I still always try to have a group of 4 when in the wilderness. I was trained back when there weren't cell phones, sat phones, PLB's, etc. You were responsible for yourself, and if something bad happened, you were going to take care of it yourself, or someone had to walk out for help. There was no pushing a button and your location is sent to a satellite and you hear a Jolly Green overhead in an hour or two.

Why 4 people in your group? It's not too big a group for disturbing primitive campsites, or trails, but, enough to deal with contingencies because if someone was injured, we'd either have enough manpower to self evac, or if we needed more assistance, one person stayed with the guy that was hurt, and 2 others walked out for help. This way, a couple good things happen. Nobody is alone, you typically would have 2 tents so both groups would have shelter if you are multiple days away. You would also have 2 stoves, etc. 4 people can carry their own gear, but, each can also carry a little extra group gear, so you probably have better cooking, first aid, and shelter than the spartan amount you tend to take solo.

I have also hiked alone, and feel fortunate that I never had a bad injury doing that, it was always very enjoyable. I agree that there's a peace and solitude doing that; it's great mental floss. Having said that, I haven't solo hiked since I got married and had a kid. I guess I just won't take that risk with the responsibilities I have now. When I was doing SAR in college and beyond, I saw examples of too many ways that solo hiking could put you in a very bad scenario. I would hate to have my wife or son try to figure out after the fact why Dad would ever take that kind of risk when he had seen so many people get into trouble first hand. It means I don't have the solo solitude, but, I think the trade off is appropriate for where I'm at in life right now.