Cash back is already money
A 2% cash back card returns $2 per $100. That number does not change with how you redeem it.
Cash back cannot be devalued after you earn it, apart from rare program changes.
For many households, a simple cash back setup earns close to the maximum with no work.
Points need a valuation
Points are worth whatever you redeem them for. Cashing out often pays one cent each or less.
Transferring to airline or hotel partners can return more per point, but only for specific bookings.
A 3x points card is a 3% card at one cent a point. At two cents a point, it is a 6% card.
Compare in one unit
Convert every card to dollars per $100 using one valuation, and use the same valuation for all of them.
Choose a conservative valuation, such as one cent a point, unless you have a record of redeeming higher.
CardSwipe ranks cards in dollars per $100 for exactly this reason.
