Steve is a hypothetical PC with 20 levels in Wizard and an intelligence modifier of +5, and as such he can prepare a total of 25 spells every day. He also has all spells a Wizard could ever learn in this spell book, due to a DM who is really generous in giving out spell scrolls.
If he sits down and prepares all possible 9th level spells and as many 8th level spells as he can in addition to that. Resulting in him spending 9 minutes each preparing 16 9th level spells (from the PHB, XGtE and TCoE) and 8 minutes each preparing 9 8th level spells. This results in him spending a total of 216 minutes that morning preparing his spell list.
Has Steve spent the most possible time imaginable to prepare his spell list, or is there any way for a player character to spend more time preparing their spell list than Steve did?