The $2->$20 bump was entirely the result of WallStreetBets pumping and others bandwagoning, but it's not an unrealistic valuation. It wasn't completely insane like GME. AMC only went up to $20 for one day (near its Oct 2018 price) and is now at $8.28 (roughly where it was at pre-pandemic).
Sadly for me I had it on deck as my next pandemic-recovery bet in January, waffled for a few days, and then those nutjobs at WSB ruined my plans.