prior to right-wing appropriation in the 1960/70's.

Because when its been this way for long enough to be considering retirement, the way it used to be is pretty irrelevant to the discussion.

It's like calling Republicans the party of Lincoln. It has no connection to today's politics.

Libertarian is the opposite of authoritarian on the political compass. It's a shame that it's had a phase shift in meaning and most people assume it's right-wing libtertarianism, i.e. turbo capitalism with no rules/regulations.

100% this. And it's sad. Because there actually aren't any right wing libertarians. They are (economic) liberals. Rejecting basic tenants of Libertarianism like public ownership of natural resources , and tack on insane BS like the NAP. The man who coined the term libertarian, defined what it was, fought in the fucking French Revolution. He also rallied and fought against the same Liberals larping as libertarians today.

it's easier to pick a different corporation (i.e. don't buy from them)

This argument also falls apart when the thing you want to buy is essential and/or all of the companies selling it are horrible (or the very concept of selling it at a profit is horrible), e.g. health insurance, water, housing, staple foods, and so forth.

We have cooperatives in a lot of forms being part of our existing system. This is in the form of housing coops, cooperative banks, cooperative stores and worker owned companies. All of them survive and some even thrive in our current system. Mostly they are growing slowly, if at all, but are much more stable and fiscally conservative. They can even work very well on natural monopolies as utility cooperatives have shown.

There are also legal setups like trusts, which can be very benefitial, if done right.

Hear me out: Instead of companies we have various non profit organisations that evenly supply people with goods and have to keep their expenses completely transparent.

I'm sure there's some issues with this and I'm curious to hear them but I feel like this would still be far better than corporations and especially monopolies or oligopolies trying to take our money. (I hope it's clear that these organisations wouldn't have to be like existing ones just operate similarly and I don't care about it not counting as a non profit organisation in some existing government.)