Your distrust of the middle-class isn’t completely unfounded, I don’t think, as it’s very easy for middle/upper-class folks to be manipulated into believing that policies designed to benefit billionaires/corporations are also of benefit to them.

It’s not about people being manipulated; it’s about the fact that in aggregate people will vote for their class interests. This is why the country’s most successful left wing bourgeoisie party, the Greens, is basically a NIMBY party who spend most of their time strongly opposing green development. Their members haven’t been manipulated, they’re just voting in their own interest as, by and large, wealthy homeowners. Labour, because it still has some funding from the working class as working class people is capable of proposing policies that will, e.g., allow more housing and green developments, while the Green party just isn’t. That’s class politics at work, and that’s why we need Labour.