It's an Israeli company, the military has such a strong influence on formation in this society that being offensive (for European standards) is considered a virtue.

I have many friends who came back (often after visiting family) and complained about the "lack of good manners"².

See also Getting behind Israeli 'frankness' ¹

IOW many don't shy away to risk talking bullshit, they expect you to talk back and give them reasons to shut up.

In this sense, Mr Rubin yes you are a prick who didn't do his homework and this unprofessional talk will backfire on you! :)

¹) Though after reading this blog Are Israeli rude I see Central Europeans somehow in the middle between Israeli rudeness and American "passive aggressiveness" ... of course well balanced! ;D

²) politely phrased (pun intended ;)

update

see also Haaretz # Can Israelis learn to have better manners?