Siri is easy enough so we never looked much into it, but “OK Google” for instance looked like a real PITA, so we did some research before buying an assistant.
It appears a ton of people just intentionally say “Ok GooGoo”, “Ok Boogle” etc., whatever is easier for them to pronounce and it works perfectly fine.
It’s a genuinely hard problem to solve, and I am willing to give the benefit of the doubt to Apple for instance when they have humans reviewing samples. There may be other motivations, there’s ton of people in any of these companies, any given feature must be seen from a different angle depending on the department looking at it.
But I think a lot of what we see as privacy violating is primarily an effect of the flaws and all the hacks needed to make the feature work at all (when it works).