In my opinion, despite hundreds of hours of Bitcoin podcasts, articles, books, etc. unlike the Bitcoin network, the future of Bitcoin's value and salability is not as certain as many here believe, so I wouldn't make myself dependent on being able to sell off BTC to not live on the street. But neither would I want to have 0 bitcoin. (EDIT: 0 point something is OK, I meant none at all.) I would spread my risks.

(The future of the housing market, however, is certain to crash, the only question is when.)