1.) 5e casters get much more powerful cantrips than their 3.5e/PF1e counterparts. When out of spell slots, they're no longer limited to using a sling or casting acid splash for a whopping 1d3 points of damage.
2.) 5e wizards can cast ANY spell they have prepared, whereas 3.5e/PF1e wizards had to prepare specific spells in specific slots. Don't underestimate the power of flexibility - a level 20 5e Wizard can have multiple 6th-9th level spells prepared and choose the best one for the situation.
I prefer to cast time stop four times a day and could do without cantrips. I guess they canceled time stop in 5e? Did they?
