https://www.businessinsider.com/why-nigerian-scam-emails-are...
(1) Sending email is nearly free, creating devices is not. Not sure if the economics match.
(2) False positive filtering matter because spammer need to manually reply to emails, creating more work. But with these devices this is not the case, it's all automated. There is no need to filter out smart people.
Job titles do not have consistent meaning across regions or industries. People use buzzwords and hype to recruit funding and talent.
You've learned an important lesson: use interviews to gather information about companies and teams. "Can you describe in broad strokes a typical project for this role?" is a perfectly reasonable question to ask a hiring manager.