I see them as, in a very basic way, as being quite similar. Two steps forward, one step back, if you like; with achievement of goals not always guaranteed and certainly not always happenng in a straight line from start to finish.
I agree about the sense of continuity. However - and this is I think where we differ - for me that continuity includes within it rises and falls in fortune as time goes on. A character might do spectacularly well in its first few adventures, then fall on hard times and lose a bunch of stuff (levels, items, whatever) over the next few, then rebound and make a comeback...etc.
You, if I'm reading things right, seem to want to take out the "fall on hard times" piece.
Only if the players and-or PCs care about such things. Some do, some don't, and it can vary even within a single player or character i.e. they care about plot element X but not about Y.
Leveling up isn't even always a goal. Becoming powerful within the setting (which almost directly equates with getting rich, in most settings, much less so than just levelling up) almost always is.
We run in different circles.