Sorry dude. I've got a lot of criticism of Niantic, but this is entirely, 100% on the players who think they can solo a Rank 4 Raid Boss. When the estimated number of trainers needed to take one down is 17 (like with a Charizard), you have to be an absolute moron to think you can do it solo.
Maybe - MAYBE - Niantic could make a bit bigger recommendation message when you're looking at the loading screen. Maybe they could make it stand out more. But it's there - I saw it right away when I logged in to my first Raid battle. It was plain and obvious and I was under no illusion that I could do it Solo.
So no. Can't agree with your post in any way.