I'm a model 3 reservationist. Like most of you, I'd like to be able to get ACC at a lower cost, like $1k.
I'm in the market for a new car for my college-age daughter, and have been shopping VW. I can get a near top-of-the-line Passat for 26k, which includes their "Driver Assist" package, including emergency braking, lane assist (stay in lane), blind spot monitoring, and adaptive cruise. Did a test drive, and the features worked pretty well (didn't test the emergency braking). The hands-off lane assist kept me in lane through normal highway-grade turns. And the ACC recognized speed changes ahead and adjusted well. Having said that, the Model S that I test drove did feel more sure and smooth in those functions.
The point, though, is that these features are available on less expensive cars bundled in less expensive packages. Tesla is significantly ahead in implementation and performance of these features, but I think they'll have to make them (or subset of them) more attainable cost-wise to maintain and expand on sales beyond the first 400k wave, where buyers are a little less enthusiast-level, and a little more conscious of features for the dollar (or the k-dollar, as it were)