Does anyone know the breakdown of retail crypto that is kept on exchanges vs cold wallets?

I'm guessing majority (>>50%) is kept on exchanges, especially now with Robinhood and Coinbase which are two multibillion dollar publicly traded companies.

Also is it fair to say that if you have let's say 100K in Crypto, that the paper your pass phrase is written on is the equivalent to a 100K bill, you lose it or it gets stolen then POOF. The hardware wallet key fob itself is worthless.