Another comment mentions this classic meme:
> Consulting service: you bring your big data problems to me, I say "your data set fits in RAM", you pay me $10,000 for saving you $500,000.
A lot of industry work really does fall into this category, and it's not controversial to say that going the wrong way on this thing is mind-blowing. More than not being controversial, it's not confrontational, because his comment was essentially re: the industry, whereas your comment is directed at a person.
Drive by sniping where it's obvious you don't even care to debate the tech itself might get you a few "sick burn, bro" back-slaps from certain crowds, or the FUD approach might get traction with some in management, but overall it's not worth it. You don't sound smart or even professional, just nervous and afraid of every approach that you're not already intimately familiar with.