Honestly, the best street wear option against a blunt weapon would probably be motorcycle gear. That stuff is designed to take hitting the pavement at speed and keeping you in (more or less) one piece. Technically, it’s not “soft armor,” since it’s reinforced with solid plates. But it’s in the same general area.
That said, any padding will help against blunt force trauma. But, all a normal padded winter coat will help deal with is unarmed strikes. It won’t really protect you from a crowbar or baton. It will protect some, just not enough to matter.
With a Kevlar vest, I’m not sure how rigid those things are specifically. If you’re taking a blow directly to the chest, it should absorb some of the force, though I’m not sure exactly how much. ProRonin and Skypig would be the people to quantify that.
Except, it probably doesn’t really matter, because of how people actually use blunt weapons.
The common attacks with blunt weapons are strikes to the shoulders, arms, and head. You draw back and strike in towards the silhouette of your target. …and a Kevlar vest doesn’t protect any of those areas. It’s designed to save you when someone tries to shoot you in the chest, not when they’re swinging a baseball bat at your head.
You can perform a thrusting attack with a pipe, but, if you know someone else is wearing armor, it would make more sense to just strike around it. Incidentally, you can’t perform a thrusting attack with most telescopic batons, since you collapse them by striking against a hard surface. Incidentally, a quick thrusting strike is one of the most devastating things you can do with a baseball bat in combat. It delivers most of the force in a fast short motion that’s almost impossible to avoid. But, the kind of person that knows to do that is also probably the kind of person that would choose to strike around armor.
I would be genuinely surprised if a vest actually offers less protection against a knife than a leather jacket or shirt, but, some of the same considerations apply. Knife fights usually end based on injuries to the arm before following into a killing strike at an angle that would bypass a Kevlar vest, rather than trying to stab through it. And, while I’m not completely certain, I’m pretty sure an “aim for the kidneys” shanking from behind can be performed at an angle to bypass a vest.
Ultimately, we’re talking about trying to use the wrong kind of armor for the situation. Most riot gear won’t protect you from someone shooting at you, but it does wonders for someone coming at you with a sledgehammer.
The opposite is true of Kevlar. If someone’s shooting at you (and they’re far enough away), it should keep you breathing, but it’s just not going to help you when dealing with someone armed with a baseball bat, frying pan, or whatever else they managed to dredge up from their home.