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The landing recovery has a special property which allows it to be "canceled"/skipped depending on what you do. At the first landing frame, it's not possible to jump again (i.e. can't go directly to the prejump animation), to have a move to startup instantly (normal and special moves) or to block (which is why sweeps can be used as anti airs in this game), but you can do all that on the second landing frame. Throws are an exception and can be performed on the first landing frame(not the first ground throwable frame) and this includes command throws too, but since the hitbox-hurtbox interaction have priority over the throwbox-throw vulnerabillity box interaction, this can't be used as a counter to well timed anti air sweeps. You'll only be stuck for the entirety of the landing recovery if you want to walk back/forward.
Things are different on jumps that crosses over the opponent (landing on the other side) though. In that situation it's possible to walk back/forward, to jump again or to even block on the first landing frame! Strangelly, if a throw is timed on the first landing frame of a jump that crosses over, a throwbox will never come out, even though that input will result in a normal coming out 2 frames later (like it normally would). Anyway, being able to block on the first landing frame can help a little bit on some safe jump crossup setups, or maybe in other situations as well if your character has a huge jump arc.