It is possible that Bitcoin price reach $250k, but it will soon after that drop under $100k. Also I would speculate that more possible time frame is 24 months and not 12-18.
The same pattern as it did with its past all time highs. $250k is such a huge amount to think of and IIRC, there's one famous crypto guy that has predicted this, Tim Draper.
(
https://cointelegraph.com/news/tim-draper-doubles-down-on-his-250k-btc-prediction)