What type/models of hardware wallets would exchanges use?
Some have like 100k bitcoins in hardware wallets. How do they keep the qctual wallet from being compromized. They surely cannt let anyone even the owners tranfer funds outside from it or even hold it

Thats open to criminals chasing people with access to those wallets even if the employees were honest they are still under risk if they have sole access. So what type of hardware wallets would they use?
I see ledger has a wallet that can have multi seed access and transaction size restrictions but thats something new, surely there was a solution before ledegers one.
I guess as long as you have the pass phrase for your wallet it is not a problem if you will physically lose your hard wallet. We don't actually know how exchange keep their assets and users' deposits safe on their end. I think they have prepared several measures on how will they store huge amount of crypto even before they have launched their exchange.