That's a scary thought, isn't it.
It's a tall task, for sure. Hell, if things don't break right, we might need two. I'd bet Seidenberg bounces back at some point and could fill the #2 role next to a star...or I'm wrong about Hamilton and he grows by leaps and bounds into a wholly reliabe top pair offensive defenseman. The Bruins really need one of those, at least.
Sadly, this is likely true; whether he'd even waive his nmc, he's damaged goods at a high price tag.
They say, in real estate, "you make your money at the buy". Chia was insane to think this guy would still have been effective in his late 30s and early 40s. This downturn shouldn't be a surprise to anyone. You don't see many 40 year old NHLers, nevermind effective 40 year old NHLers. Really too bad.
I hear where you're coming from. His warts will become more evident. But I really don't sweat Chara as a #4 until he calls it a career, which might come before the contract ends. His reach will always be there, and he'll always be big. The guy next to him will be Important, be it Seids or Dougie, if I'd guess. They need to rebound and get better.
In the end, the Bruins should worry less about Chara and more about the guys around him. Some of those top guys aren't here.