What are Braum's weaknesses in lane?
Given that I main support, I find that Braum becomes a thorn on my side no matter what type of support I'm playing. Good Braums will save their jump+shield to nullify anything that can result in a kill (Nami bubble, Nami ult, Morgana dark binding, Leona zenith blade, Thresh/Blitz pull, etc). I can work around Morgana's Black Shield. Sure, having my bubble not CC the ADC sucks, but she can't blackshield two people at once, so my Nami ult will CC at least one person. Braum just spends the use of one ability to completely nullify anything you throw at him, and a good Braum will hold on their jump and shield for when they are actually needed (whereas most bad Braums will just waste them impatiently because they can't play the waiting game).
And that's not even counting the true source of my frustration: the passive. It's a deathmark. If you are hit even once and he's in a position where the ADC can follow up, you're dead (unless you're Leona/Alistar, in which case he "merely" takes three quarters of your health). Lucian in particular is a horrendous ADC to face with Braum, as his passive lets him fill up Braum's passive faster than any other ADC and his dash means that he's more or less always in a position to follow up on Braum when he tags someone. I just don't understand how to deal with that. He doesn't really need to hit his Q, he's tanky enough to just walk up to you or your ADC and autoattack. It also doesn't seem to matter how much damage you pour on him, he seems to have Alistar-levels of tankiness, and if you back off to avoid the autoattack, he's effectively zoning you and your ADC simply with his presence.
He's also the only support with a dash to safety. Every other support with a dash is enemy-targeted (Leona, Alistar, Thresh). It doesn't matter how much harass he eats for the price of zoning you and your ADC, he can simply jump to a minion and escape retaliation, whereas any other support that attempts to do this can actually die. Even if you get him low enough to be finished off by your Cait/Ez/Jinx ult, he simply shields it off and then backs to base, having exchanged most of his health for several seconds of zoning you cannot get back. Letting his ADC freefarm while zoning off the enemy ADC is invaluable in the game. Being able to secure kills simply with an autoattack (again, he doesn't really need to land a skillshot the way Morgana, Blitz, Leona or Thresh do) is something I cannot understand.
How do you play against that? Braum can easily claim bush control simply by walking into the bush (even if it's a bush behind your own minion wave). If you attempt to fight him off, he just tags you with the passive and his ADC gets a free kill. If you back off, you are surrendering the bush to him and giving him zoning power. If any other tanky support were to do that, they would either (depending on the support I'm playing) get all-inned and have to back off or risk dying, or eat so much harass that they have to back off or risk dying. Braum doesn't operate like that. If you all-in Braum, he tags both you and the ADC with his passive and then proceeds to absorb an ungodly amount of damage (and if you turn your attention to his ADC, he just jump-shields to them and he still wins the all-in). If you try to harass him, he walks up to you and tags you with his passive, which means you must kite him backwards, which is still conceding him zoning power and presence.
I just don't understand what his weaknesses are and how to exploit them. He just seems like a hopeless, unwinnable situation whenever I face an enemy Braum that actually knows what they're doing (a Braum who doesn't know what they're doing is still annoying but way more manageable).