800 volts is one of those stealth benefits that seems like it is less appealing than high technology , range, performance, buying experience, resale value, safety features, charging network and self driving.  Who is going to pay more for 800  lots in exchange for all these other benefits?  I get fancy stitching and nice interiors - but the other stuff needs to be at least a little more competitive. 
When the Plaid smokes the Taycan turbo plus will the Porsche driver who almost pay double be really happy about having 800 volts or will he be pissed that Porsche is not quicker?  
Most will wait until the Porsche is quicker. It was for a few months -