Why is there so much love for the CSR (besides the 1st year bonus)?

$8000 travel (what the OP mentioned) nets $240. Subtract out the $150 annual fee and it's now +$90. Add in $20k regular spend* and we're at +$290.

A Citi Double Cash is 2%, which is +$160 on the travel spend. Add in the $20k regular spend and it's +$560.

* wasn't sure if this was CC spend or just total spend/year.

If you're redeeming points for cash, the CSR is not for you.

$8000 travel is $240 cash value or $360 travel value. All UR points (from any card) can also be transferred to a CSR for the 50% redemption bonus, so your rotating 5% categories on Chase Freedom become 7.5% when used for travel.

CSR also gives you airport lounge access, pays for Global Entry or TSA PreCheck, provides primary insurance on rental cars, and some other stuff.

$8k travel spend = $360 travel credit. $20k regular spend = $300 travel credit. $360 + $300 - $150 = $510. $50/year difference, ignoring all the other perks of the CSR (and also ignoring the $750 travel credit from the first year, which is 15x that $50 difference).

Now if all you want is a cash back card, then as mentioned - the CSR is not for you.