Been in further communication with them.
Either it was a lame attempt at gas-lighting or they are just way incompetents'.
They kept alluding to the "numerous times we contacted you"- on pressing for details, turns out they sent a single email in 2016 to someone they thought was me but wasn't.
I then presssed about the "Incessant slanderous comments" i made. It consisted of two- one pointing out the triplane config was chosen because the founder's (who was in marketing, with no engineering or physics background) father had built an RC model in that config (I sh1t you not!!) and another where I thought it would have a 5:1 L/D ratio (NO!!! they have wind tunnel testing showing it's 12:1!!!).
So, yeah- I think they've worked out that no matter how ardent a critic, bringing peoples families up is not a good look.