In gross terms, crypto is tiny compared to the dollar/euro banking system, so it's likely to be a much smaller number.
Interestingly, for those who use crypto as-designed, the percentage lost to bank runs is almost nil since you 'hold your own coins'. It's people who leave their money on crypto exchanges that lose their coins.
People who hold their own coins lose them as well. It was estimated that 3.7 million bitcoin have been already lost irreversibly [1]. That's a staggering number. It's roughly 20% of the entire supply.
[1] https://blog.chainalysis.com/reports/bitcoin-market-data-exc...
I don't see why I should take this seriously.
The vast majority of traditional currencies have lost nearly all of their value over time, including the US dollar.