If you focused on any of the trees singularly then of course you will have points to spare. Go hack through the whole game if you want but its still a combat skill if you use it against people. Hacking a person across the room so they "turn off" is little different from poisoning or trapping them.
Not sure if i agree. Deus Ex had separate skills for: pistols, rifles, heavy, low-tech and explosives, meanwhile combat in Deus Ex meant that you fucked up beyond belief, and in reality you could beat the whole game with maybe 2/5 levels in pistols and explosives at most.