Page-flipping is perfectly possible at full framerate on both machines (well, any machine really), only limit is of course the available memory. I'd say the piece of Amiga-software you tried was limited or badly coded, because there's no reason for page-flipped animations to be less than full framerate.
So no reason to blame chip-ram or the clockspeed, a page-flip takes a few cycles and therefore doesn't require any CPU-power at all.