I flashed openwrt to my spare mikrotik cap ac I had laying around because I need to do some testing with some vlans.
After flashing it appears to be using swconfig on 22.03 and I was hoping it could do dsa.
Is there a way to use dsa on the mikrotik cap ac without having the "Switch"?
If we're talking about this device, ipq40xx has switched to DSA in master, after openwrt-22.03. So just upgrade to a current master snapshot and you're set.
Awesome!
Snapshot as of tonight is up and running on the cap ac and that swconfig is now gone 
Next question for anyone with the knowledge.
When I ssh into the cap ac and run "ip a" I see the "lan" and "wan" interfaces prepended to "@eth0".
There are two physical ports on this device and I was hoping to see at least physical eth0 and eth1 devices like my other 2port wap.
What is causing lan and wan to be tied to eth0 instead of eth0 and eth1 or at least eth0.1 and eth0.2?
ipq40xx has only a single physical CPU port, the second one was only a fake invention of the older swconfig driver to make it similar to other devices (with all the problems that hardcoded VLAN tagging entailed), there really is nothing else than that.
To your last question, DSA, the mere concept of it.
Thanks for your time. It's superficial but for me I have preferred to keep my "interfaces" ( luci > network > interfaces > interfaces ) represent the actual name of the network they are serving and "devices" ( luci > network > interfaces > devices) represent the physical ports they are tied to ( if that makes sense).
My curiosity will still be lingering since I have a working netgear wac510 on 22.03 and it shows its two ports as eth0 and eth1. Even more curious is the board.d/02_network file inside the wac510 lists the mikrotik cap ac as being set to "eth0" and "eth1" for the lan_wan interface set command but the snapshot I installed shows the cap ac as being set to "lan" and "wan".
Just a superficial observation. 
In DSA the internal port eth0 isn't usable directly. This is because the hardware traffic in and out of eth0 is specially tagged in order to have a 1:1 connection to a specific external port, which is replicated to a set of virtual ports that funnel into eth0. The tagging method varies with the vendor of the switch chip and is intended to be opaque outside the kernel.
So make connections using the names of the external ports.