Hmmmm,
Only a little while ago Bitcoin was somewhere around $12K-13K, now it's sitting around $9k. Do you think it's a good idea to invest cash in Bitcoin at this time hoping that in six months to a year or two it'll raise up again ?
Ain't got a clue. Anyone who claims they do have a clue is a bit of a twat. In general though there's no sign of Bitcoin's spread running out of steam. If you sit there long enough then the chances are good things will happen eventually.
I think it's a good idea if you don't need money right now and you don't have to see the profits in a month or 2. Bitcoin will become worth more than it is now, if you don';t believe me, read some opinions from the well known market analysts. What we don't know is when it's going to happen. It can be a year or it can be 5 years.