In general? Yes. But it depends on the nature of the startup. VC-backed startups are not more trustworthy at all.
However, there's a rather huge difference in the capacity for harm. If Joe's Tiny Company is just as nasty as the likes of Amazon/Facebook/Google/etc., JTC is still preferable simply because they don't have as much power to abuse.
Startups are even worse - most seem to care only about growth, not even profit, their goal being to hand off the hot potato they built as soon as possible, to whoever gives enough money.
However, there's a rather huge difference in the capacity for harm. If Joe's Tiny Company is just as nasty as the likes of Amazon/Facebook/Google/etc., JTC is still preferable simply because they don't have as much power to abuse.