The only reason I think this matters is their finances are a lot different than a tech company. You are correct that Tesla is currently priced like a tech company though, so maybe I'm way off!
Apple dropped the "Computer" from its name when moving firmly into a market (pocket supercomputers) which was a natural extension of its real core competency (high-UI/UX computers), but which (phones) were deeply perceived by the public as something profoundly different from "computers". Steve Jobs rediscovered the company's core competency, focused on it, and adjusted name & strategy accordingly.
Kodak thought its core competency was photochemical consumables. That was a pivot away from imaging, and into oblivion when the imaging technology shifted.
Smith Corona's competency was typewriters. We still need typewriters, but because SC tried to compete with computers (a spreadsheet on an electric typewriter is a non-sequitur), rather than being the best product for a shrinking yet enduring market, the biggest world brand vanished overnight.
If a company is going to pivot (which a name change absolutely signifies), then it better pivot around its core competency. Tesla's "tech" need be absolutely about either electric cars (by which batteries and solar are incidental and expendable for more suitable power sourcing), or solar (by which the consuming device may be far different than just a car), or power storage (source and use of power being incidental). Tesla is only "tech" insofar as they're pushing the limits of technology for building & powering electric cars. Stick with the cars, with solar ONLY as a means to free their power sourcing (and extra powering one's home), and they'll do fine; self-identify as a "tech" company, and they'll die of confusion. Musk is smarter than that mistake.
For me a tech company is any company that uses the development of technology as a competitive advantage. Solar is not, major solar companies are not developing innovative technology. Tesla is, they do not have an advantage in scale or low prices, but have advantage in how their vehicles function.
