Ralif Redhammer
Legend
Like I said, I suspect the way people used Spelljammer and Planescape varied from gaming group to gaming group. Some people saw them as means to an end, others as the destination themselves. Regardless, I think both groups can agree that they're more interesting when there are places you can go. Both had many books released in 2e. We're not going to get that with 5e, which is why I think part of whatever we get is going to have notes on moving from one 5e setting to another, whether traveling the planes or the phlogiston.
I view both Planescape and Spelljammers as metasettings, they aren't settings in their own right, they merely connect settings, the means to move between them.