I see from the EV my parents bought, they got for 22k euro, a car that does 240km on paper. Now a few years later, you can buy a BYD for 26k, that does 450km (ext version) on paper. That same BYD is WAY more fancy, tech gadgets etc...
But that is comparing a lower market segment where this effect is stronger.
On the higher end market, where the Tesla's used to dominate, we see less movement as those cars already came with tons of tech, and large batteries.
Thing is, i am still not buying a EV despite them being better. The same arguments we had with EV disadvantages is still present today. I rather buy a second hand gasoline engine simply because of the convenience of the default 600 a 700km range on most vehicles, the 5 minute tank job, the lack of charging in the city, the prices despite the heavier depreciation in the second hand market are still worse.
Ironically the gasoline car we bought 10 years ago, for 7.5k, still sells today for 8k in todays market (added 50k kms on the car). So even if we take a cut, the actual gasoline engine depreciation is strangely less strong. I track several gasoline cars where i had a interest in from years ago, same phenomenon.
For some reason you expect gasoline cars to drop more in pricing because now in EU 17% of new cars sales are EVs and 36% are hybrid. So more gasoline cars on second hand market? No ... because people are also buying less cars because of the economy, more work from home etc. Resulting in actually less second hand cars as people hold on to their vehicles longer, waiting out this transition periode.