Is that really accurate? I've heard that the tech sector in Montreal is actually pretty lenient about English, and there's ways startups get around bilingual regulations by mainly catering to American/Anglophone markets, which is a loophole they can use. Have seen a good amount of commentary saying that programmers in Montreal don't need to speak a lick of French for their jobs.
I'm not saying it is impossible, however bilingualism is often required in Montreal. Also, once the startup gets to a certain size(I'm not sure if it is over 30 or 50 employees) they have additional restrictions imposed by the OQLF.