and is even now FDA-cleared for clinical use: e.g. https://www.bio-beat.com/post/the-biobeat-cuffless-wrist-blo...
Pulse ox and HRM such as Apple Watch and the cheapy blue and white finger readers are ubiquitous and not absurdly inaccurate (usually).
To the GP's point, the largest blood pressure monitor company is Omron. Portable monitors have been around. https://www.omron.com/global/en/technology/omrontechnics/vol... is a good place to learn more about the advantages and disadvantages of different approaches. Piezoelectric and PPG would have the advantage of lower cost, lower mechanical complexity, and continuous monitoring instead of point measurements.
Not reliable/valid cuffless monitors, though. That's relatively new, if I understand correctly.