I think you guys are over-reacting about Fire Jab a bit.
It's more unreliable, yes, but pretty much only at lower percents. I've had no trouble consistently landing Fire Jab when I need to score a kill at the 100-130 area.
No, I've been testing it quite a bit. You've probably played against people that are unaware that fire jab has been changed, or on Wifi, where it's harder to time some of the escapes.
The fire jab doesn't
true-combo until around past 150-ish% on medium weight characters(you can easily test this in training mode). What does this mean? Every single character in the game has a way to avoid the fire jab until that %. Characters with invincible moves, for instance Mario or Sonic, can Up B out of your firejab and punish you 100% of the time. Certain characters(typically smaller ones) can jump out of it while airdodging pretty easily if you time it correctly. Then, some of the other taller characters, like Greninja, you can merely hold down on the control stick and hold shield and you'll block the fire jab and be able to punish every single time.
Again, this is all only while they're under 150-ish%(pending their weight), however. Opponents don't typically live to 150% when I'm playing as Robin. Plus I wouldn't call any jab that doesn't work against ANY character lower than 150% reliable in any way.
If you know your opponent will get out of the wind and fire jab, you can alternatively just stop mid-hit, and look for follow-ups. If they're DI'ing out, it has to be up and away, so you can follow up with Fairs or just reset neutral. There's usually enough warning to recognize when an opponent will get out to do this.
Actually, no. I'll give you an easy example character to test with, who I already mentioned; Greninja.
Have a friend play Greninja. Have him hold down on the control stick and shield button. Then go ahead and try to 'mix him up'. If you fire jab, he'll block the hit and be able to grab or jab you. If you do nothing, he either grabs you or does an aerial out of shield or whatever. Then finally.. Wind jab. This is the only semi-safe option and only because you won't get punished 100% of the time for doing it. Even then, you can potentially be punished for using it against him. Since he was holding down and shield, he won't block in time because jab2->first hit wind jab is a true combo most of the time. But as soon as he sees the wind jab come out, he can let go of the shield button and down on the control stick, and instead smash DI away from you. Sometimes he'll be able to get out of the multihit and then attack you after you perform the final hit of the wind jab.
Fire jab really just doesn't work if you're playing against intelligent players.

I can make a video showing how unreliable it really is if you'd like, but if you teach your friends how to punish your jab usage, you'll be able to better understand it for yourself.