These one page "we make the rules and can change them at any time" contracts are bogus. There's no accountability, no fairness. Things become arbitrary. There's no accountability when the company violates it's own policies.
It’s hard to disentangle these, unions are effectively the only way for non-executive[0] employees (in the US) to get an employment contract that isn’t one-sided in favor of the employer. The primary function of a union is to obtain a contract.
[0] I highly recommend reading the “Executive Severance Plan” section of any publicly traded tech company’s SEC filings, they are fascinating.
If they were actually one-sided then no employees would sign them. It's not like there are no alternatives to finance tech.
I've become cynical. Every job seems like it's the same shit with the same problems and there isn't anything better.