I don’t understand what GW is doing

Context: im just getting into 40k and black templars. Hopefully finishing assembling my combat patrol today!

My idea of fun is minis brawling and I don’t understand what GW is doing with “actions” as a game mechanic.

Since they restricted access to Purge the Foe, If I understand correctly, my knights with master crafted power weapons will be sitting in a ruin, not fighting and downloading a file? Triangulating? Wtf??

“Just buy filler units to do actions” is not a good answer really. GW is telling me that I must spend money and time on painting and assembling units that i don’t want and then pay points tax and a mental tax on it during gameplay.

Other solutions are: finding a casual random opponent who’s cool with ignoring GW rules about disposition limits, accepting that Companions of Vehemence = Black templars or lastly being fine with fielding a non competitive list. Non of that sounds like fun tbh.

Maybe I’m just a clueless noob who’s missing something. Maybe i came to this game an edition too late. IDK.