"Given we are so close to year-end, we are not providing any updates to near-term price objectives—read this as, we are tired of people asking us about target prices," Lee, former J.P. Morgan Chief Equity Strategist, said in a note to clients.

For the last time this year, co-founder of Fundstrat Global Advisor Tom Lee updated his estimate for what a fair price for bitcoin should be: Between $13,800 and $14,800. The model still puts bitcoin about $10,000 above where the world's largest cryptocurrency was trading Thursday.

The best-known bitcoin bull on Wall Street is getting tired of forecasting short-term prices.

In November, Lee cut his price target from $25,000 to $15,000. A key driver for the revision was bitcoin's "break-even" point, the level at which mining costs match the trading price.

Bitcoin is closing out a miserable trading year. The cryptocurrency is down 75 percent since January, trading near $3,324 on Thursday, according to data from CoinDesk. From its high near $20,000 in December, the cryptocurrency has lost more than 82 percent of its value.

For bitcoin to stage a price rebound, Lee said user adoption needs to increase, and it needs to be embraced as a real asset class.

But looking out longer term, if the amount of bitcoin users approached even 7 percent of Visa's total 4.5 billion currently, Lee's regression model would place fair value at $150,000 per bitcoin.

"Hence, the risk/reward is still strong," Lee said. "Given the steep discounts of [bitcoin] to our fair value models, the excessive bearish sentiment about fundamentals does not seem warranted."

Still, Lee said technicals remain important in cryptocurrency trading and as long as bitcoin remains below its 200-day moving average, investors will likely still stay bearish.