The shortest bear market?
There were actually several short bear markets, some even shorter than the current one (if the bottom was already in):
- 2011: June to November (5 months) - loss: ~93% from previous high ($32 to $2)
- 2013: April to June (2 months) - loss: ~80% from previous high ($260 to $50)
- June 2019 to March 2020: (9 months) - loss: ~71% from previous high ($14000 to $4000)
- May 2021 to July/August 2021 (2 months): - loss: ~50% from previous high ($60000 to $30000)
- to compare: October 2025 to February 2026 (4 months): - loss: ~52% from previous high ($126000 to $60000)
The May 2021 bear market is actually perhaps the most "fitting". At least, there are several bearish movements which would not be that different from the current one. Of course, if you're a believer in the 4 year cycles, they were at different moments, and thus some would call them "not real bear markets". But as most have lead to 70% and more losses, I would definitely call them that way

There's another "expert" who thinks the bottom is in or close:
Michael Robinson. The interesting thing is that he is a "cyclist", i.e. he believes the halvings do trigger the price movements, but he believes this time at most in March/April the bottom will be in. I don't fully understand his "oscillator" model though.