I would phrase it as "Impossible to determine because we don't know actual sale prices for a statistically significant sample size." In many cases, the actual sale price is well below the advertised price.
When I have seen what are claimed to be actual buyer prices made available publicly, my sense is that Roadster prices have fallen slightly over the past two years. Which does not surprise me. EVs are highly dependent on the latest and greatest technological advances. Less than 9 years after going into production, the Roadster looks primitive compared to the current cars Tesla is producing. In contrast, most currently produced ICE vehicles are basically the same as 9 year old ICE vehicles. Currently, Roadster values are roughly half of what their new price was. A 9 year old ICE with average mileage in good condition is also roughly half of what it sold for new. Note I say "roughly"!
It typically takes several decades before a car starts appreciating because it has acquired "collector" or "classic" status, and the vast majority of car models never achieve such status, they are simply junked and forgotten.
I do not know the Roadster will ever become a "classic" and increase in value. My crystal ball is cloudy. But I do think that at today's prices a Roadster is a fantastic car if the owner is willing to accept the risk of potentially very pricey repair costs if something major fails.
