You can't step it if it's done on reaction to your poke, you will get hit. If you bait and block, you will still get hit, which is wrong.
If it’s a poke that is being RE’d, you can usually step to avoid the followup. If it’s a poke and the opponent does the full charge, you can almost always step to avoid the followup. Cervantes can step uncharged RE after having A, AA, a6, 6A, kA, B, BB, 2B, b2, bK, K, 8K, 2K, 4K, B+K, 66K, 22K, 44A+B, or DC K parried by it, for example. I suggest finding or making a similar list for your character — it’s good information to know.
Plus, RE has 6 frames of startup before it can parry anything. I very much doubt than any human player is REing i12 AAs or even i18 3Bs on reaction. (A back-of-the-napkin calculation assuming a reaction time of 268ms puts the bare minimum at i22; under pressure the number is probably upwards of i30, and this assumes that the
only thing you attempt to react with is RE, rather than processing the event and choosing a better response.) What’s more likely is that your opponent is throwing it out as a guess. Guesses can be baited or punished.
RE primarily excels in situations where you know a mixup is coming, such as when Siegfried enters SRSH or Maxi enters BL (does that still have a 50/50?). As a counter to footsies it’s pretty bad.