I ask: Have you already bought bitcoin?
Answer: No. I'll wait until he recovers.
Perhaps, this fellow is ignorant of the investments in the financial market. It is always better to buy your asset when they are cheap, that is how much profit would be made. The investor would be lowering risk by doing that also, unlike buying the asset at higher prices, the risk would be higher in that sense.
Bitcoin however follows the same principles of investment, and I believe the OP should assist in further guidance as this person is totally naive.