It is a real test and they had an independent auditor but it still may be BS. Check out this Too Good To Be True article.

I agree with your point and the tech has developed very slowly. However, there are interesting developments in the sector. Have you heard of Lightyear? If they can deliver by 2025 it will be a step toward 600 mile range.

Beyond improving battery technology solar might help reach this goal too. The new top trim Prius Prime has solar panels, which MKBHD highlighted can add minimal range. Maybe as solar tech improves they can add more panels to the car and recharge the battery faster.