I've never had a business-person come to me and say "you are building a SPA", or "we are using React." Now, they have come to me with some brilliant and also ridiculous ideas, and I've done them all, but none of those dictated a particular engineering solution.
I won't claim that it's commonplace, but I have had business people specifically tell me that they wanted a SPA because they saw it as the trendy thing and wanted their web app to feel "modern".
Professionals in any field have a responsibility to do good and thoughtful work, and to treat their field with respect. Anyone who just builds whatever crap they're told is a bad professional.
Believe me when I say that I have had hundreds of meetings where I tried to tell them that what they want is crap. But in the end it's their decision not mine. And in the end I have to make money so I build what they want. This has nothing to with me being unprofessional.