they suddenly have a 'technical issue' and suspend trading until it is 'fixed.' sometimes its never fixed and the exchange founder mysteriously disappears to Thailand or dies, or claims to start an orphanage in india. sometimes all three.

Just in case you aren't catching on here, cryptocurrencies are not the future. They are just digital tulips - beautiful to look at and comprehend, but separate from any meaningful contribution to the economic system. You can still get rich from them by hyping and selling them before people catch on more broadly.

Civilization works because of laws that are interpreted by courts and norms which are broadly accepted but not often checked/enforced. Crypto is trying to create a "trustless" future where you do not need society to coordinate and regulate. Our modern financial system needs that squishiness/trust which you get from the legal system to operate at full capacity.

Picture the suspension of a car. In our modern financial world, the legal system and regulatory institutions serve as the shocks and struts of your car. It allows you to drive fast while not having to worry about every imperfection on the road. Cryptocurency is like driving a car where your wheels are attached directly to the axel - yes it's perfectly efficient and there's nothing between you and the road, but that also means you have to be exceptionally careful where you are driving, and you can't do it fast.

There's a reason all cars come with suspensions.

They pause withdrawals while they get their coins out of cold storage.

Or if the exchange isn't fully collateralized, it's a scam and goes under.

If the blockchain gets backed up it would take a few days to get money in/out of exchanges.

I don't think there can theoretically be a run on the exchange because in theory all the deposits are there, in the exchange, in theory, unlike a bank which only had a fraction of the deposited money in reserve. A run on a crypto exchange would be great for them considering they usually charge a withdrawal fee.