If u want to watch how cav arch do against eagle, watch Viper vs Jordan in the TTL i think semis or quarters, a month ago.
It was chinese vs mayans (i think, or aztec idr), and you can watch it both with t90 casting it and analyzing it or from Vipers pov/stream watching what cav arch gives you.
Essentially, if u mass u can hit and run and trade well, much better than expensive knights that trade worse in bad numbers and if eagle player adds pike/monks, or infantry that is so slow.
Iirc there is a game that depicts how bad infantry is vs eagle in ttl again tatoh vs Daut but dont remember which round.
Essentially eagles dont have to take the fight and can raid or use mobility, while eco required is usually better for the eagle player (at least with aztec/mayan) and with infantry u always chase, cant do damage, and ur ultimate army comp with infantry is always worse.