No it doesn't. People with families (i.e. a huge portion of Disney visitors) often don't have the luxury of showing up at 6:30 or whenever they feel like it. Plus, if enough people decide to show up at 6:30 a bunch of them would still be unable to ride. It only works like that at the moment because there aren't enough people showing up that early.
See, if waking up early is a minor inconvenience how about the people who literary fly or drive across the country to experience the resort? Should Disney build a park in everyone's backyards in order to make it the most convenient thing possible?
I do not know about you, but I would much rather enjoy the park as a whole while my boarding group is inching closer rather than being in queue for 4 hours. I would argue that such a horribly long queue is far more inconvenient.
I think the main thing about the boarding group system is those who actually want to ride get to ride the ride.
Fastpass+ has created a system where people book rides they would otherwise not go on simply because it is the only thing available. This has lead to long lines for rides which have previously had next to no line. A prime example of this is figment.
If Rise had a Fastpass or staggered released boarding group system people who would otherwise not really care about the ride would reserve a spot simply because they were able to.
If you are in the park before 7:00 you are essentially guaranteed a boarding group. I rode the attraction three times. I got boarding group 103, 102, and 52. I was in the parks about 10 minutes past 7:00 on two separate weekends for the first two. The 52 was a Saturday. Unless the ride is just in a really bad mood you are for all intents and purposes guaranteed a ride.
The boarding group system basically just weeds out people who do not really care enough to ride while letting people who do really want to ride experience it all the while avoiding lines that can turn the most stable insane.
The system is an absolute win. It is far from perfect but I have not seen anyone else suggest a system that does not have more glaring faults.