For what it is worth, Trek bikes are expensive. You are probably not buying a new adult Trek bike for $300. I went to their website and they have an electric bike that is $14k and they have cheaper bikes than this one that has a throttle. I think your price estimates in your math are low but I agree with your point. One reason that can make it hard to justify an e-bike is that they cost as much as a beater car but will get stolen pretty quickly in a lot of places if you are using it to commute/run errands/do anything that means your bike will be locked up for a long period of time.

I absolutely have and drive a car - but the ebike I paid $2200 for over a year ago costs you $1500 today.

I could have gone cheaper, but I'm a very heavy guy and needed a strong frame.

After 600 miles I added another motor, battery, and controller and have since added a third battery.

I have a lot of fun, quick trips are FUN on my bike and ofter faster than my car ( 25 mph speed limit and my top speed is 28, plus I often get to park real close to the doors and can take paths I cannot or would not take a car ).

The "homeless" factor for me is that with some solar panels my fuel cost is nil. ( I don't have those, but a "solar trailer" is planned ).

It doesn't replace my car the same way my phone didn't replace my desktop - but things that I would have used a (desktop, calculator, camera, etc ) for I now use my phone for. There are a lot of things I used to usey car for that I now do on my bike, and have more fun and very little frustration. ( Other drivers often get under my skin while driving )

Conversion kits are great bang for your buck. There are some decent budget options out there too though like Lectric and ENGWE. A good bike with a conversion kit would still be a better deal though.

Maybe because you're the fourth owner of that 2006 civic? The residual value of a used car has been passed from the original owner to you. Your $1,500 is a fraction of what Honda received for it 16ish years ago.

If you're looking for a used ebike, you'll find lower prices, but they are far more rare than civics.

One thing that I forsee helping in the future is having 18650/21700 batteries be interchangeable like normal AA batteries are.

If devices had sufficiently smart BMS modules then we could stick any batteries into them without any added fire risk and they could simply alert us when one was bad and needed to be replaced. Also with regards to fire risk there are mitigations that should be standard (like what tesla does).

If there were no "batteries included" and they were easy to add it would cut the cost and the e-waste by a ton.