While it may not conform to the old school idea of “hour power” I don’t see what’s wrong with using a ramp test FTP if it serves the purpose of setting zones for an individual? Especially if it’s someone new to structured training.
It seems that aside from a handful of coaches (Neal, Seiler, etc) most everyone has moved on. I had WKO5 try to tell me my mFTP is basically my 30min power and other models have done the same.
I should mention I set my FTP based on hour power, but don’t think everyone needs to do the same.