I'm pretty sure since he was booted off the main cast in 2018 + the added redesign with the standard chassis, sellers realized people are after the older design and started price gouge him because of his demand, popularity, and design. Probably because of the funky wheel design and shorter rods.
As for the question about the price, no, Edward really isn't worth 80 considering he was produced for around 22 years. Added that for some reason whenever engines are discontinued for Plarail, give or take a year they skyrocket. (i.e. Victor, Luke, Dash, & Stanley)