Modern platforms are so good does it really matter? These aren’t the old fox or panther platforms. You’re not going to meaningfully increase stiffness or improve handling very much. The electronics obviously need to be updated but not the basic platform or powertrains.
Tesla and Musk political baggage may explain some of Cybertruck’s failure, but given their poor sales compared to Model’s Y and 3 relative declines, I’d place blame squarely on CT’s design; which includes decisions that led to a vehicle priced near $100k or higher. Tesla’s Model S and X in similar price range do not sell all that different than CT either, so high price leading to low demand is the shared common theme. And it’s not all that different for other BEV manufacturers in same MSRP range.
It’s difficult to understand why manufacturers did not see that expensive BEVs around $100k would have very limited demand. If for no other reason there are not that many rich people, especially when combined with those actually wanting to buy an electric vehicle. Between high cost, high BEV depreciation, and realistic cost of borrowing money, it’s no wonder expensive electric vehicle sales seem to be collapsing.