The 800m is 50-70% aerobic depending on who you ask. Its come out in recent years that it is a lot more aerobic than previosuly thought.
You are using more than one energy system constsantly during an 800m race. The amounts different systems are used varies depending on the runner and the point in the race.
I haven't read the entire thread, but yes you definitely should train a 400/800m guy differently than a 800/1500. BUT, that doesn't mean no long run for the 4/8 guy. If the 1500m/800m does ~90min, most 4/8 guys should probably at least shoot for ~45-60min unless they are very new and very low mileage. Even then, the continuous long run is important.
No, you aren't running more than a couple minutes for an 800m race. But, to improve and make more effecient the energy systems that are used during the 800m, you need to create a stimulus on the body. A long run is a good way to work on that aerobic stimulus. That could also look like long cross training sessions to save the legs as well.
It's also wise to adjust and change (and eliminate at a certain point) the long run as the off season and regular season progresses. It's not black and white.
Also the workouts the OP posted were absurd lol