The Meaning of Life, the Universe, and Everything.
Middle of Somewhere
The problem is, however, when using /as, it's not at the entity that's executing, that's what /at and /offset are for. In which case the replacement for out /execute now would be running three commands instead of one and looking for an unused location. Instead of executing at the target, /as will execute at the executor of the /as command. Basically, /as @p /summon Creeper ~ ~ ~ in a command block would make the player summon the creeper, but at the command block. I can think of about two uses for this. Especially with functions being added, it just seems pointless to remove an already widespread and great utility with something that just makes more effort for people and is more difficult for beginners to understand.