I have the same concerns that people (cough, USAF) will say exactly that - thus the reason to list the CVL's as the centerpiece of the ARG, they just happen to have catapults.... But yes, same concerns...
I didn't think about this earlier but numerically more, but less capable ships = more problems for amphibious operations. You can tetris the hell out of a amphib, but making it shipboard compatible is only one part of the equation. You have to get it off and in the proper order to put ashore. While easy to do when every ship has a well deck, shit gets complicated when you can only move things by air and/or need to reposition stuff at sea. An LHD w/ a well deck and LCACs provides flexibility. If you start spread loading things across multiple ships, you run into serious issues executing large scale operations due to efficiency/logistical issues. Even more so if you start doing more split ARG operations like we have recently. You need all of your 777 tubes to make an effective battery, all of your CLB dets to supply Class 1/3/5 DoS and breaching capabilities for the battalion. Throw in a peer adversary with the ability to interfere with C3 and you have a receipt for a shitshow. The Falklands War is great excerpt on why it is important to have a dedicated forcible entry fleet. It's not as easy as plug and play.
I just threw up in my mouth a little bit having flashbacks about EWS.