I think there's a pretty frequent cycle when someone first "discovers" the credit card world. You apply for a bunch of cards....one for dining, one for gas, one for this, one for that. You end up with a ton of cards. You later realize some of them are redundant with your spend level, so you cull down to the ones that are useful for everyday spending. I think people often find themselves overwhelmed with the number of cards they end up with, especially when they previously may have had 1-2 cards.
Chasing CLIs has never been a huge thing for me, because there's diminshing returns. If your utilization is low, it's low. You don't need a ridiculous amount of padding. YMMV with spend and income though. If you go for excessive CLIs with a particular lender you can wind up having trouble getting approved for new products with them although you can often move limits around to compensate.
There's always been a "flavor of the month" card; Double Cash, Venture, Merrill+, Amazon, etc, etc. It's important for one to consider if the card is truly useful to them or if they are just following the excitement of the crowd.
