Likewise, I see your point. Regardless I do think a 300hp and 400hp version of the Z will still undercut their Supra counterpart. Nissan hasn't spent anywhere near what Toyota has with R&D. Historically the Z has been priced lower as well.
As others have said, let's just wait for official numbers.
Toyota Supra review: it’s a BMW with a Toyota badge
https://www.theaustralian.com.au/weekend-australian-magazine/toyota-supra-review-its-a-bmw-with-a-toyota-badge/news-story/7f941d0c93db2a55f0f20fb9889252c5