In a libertarian society, the only function of government is to prevent, discourage and prosecute anyone who initiates violence against others. As long as workers are free to quit the company they are working for, it is hard to say they are being exploited. You may consider a factory in a developing country is exploiting its poor workers, but as long as they are free to leave and find other means of support, one has to assume they are working in the factory because it is the best option available to them. One might ask if the current or previous governments are responsible for the lack of better choices.

You could own a share of the company you work for. It is a simple matter of your employment agreement. If all you agree to is to trade your labour and/or brains for money, then you should be happy with the money. I worked for two companies that agreed to give me shares of the company in exchange for 10% of my pay. If you don’t like your “totalitarian” boss then you are free to quit and find a better boss.

As long as a company has to compete for customers (unlike a government-mandated monopoly) they will want to keep as many as possible, and will do everything they can to keep their products from harming them. Their insurance companies also have an interest in helping them avoid claims. That’s why the insurance companies have boiler inspectors (to reduce the number of exploding boilers) and why they created Underwriters Laboratory (to set standards for electrical wiring and appliances to reduce the number of house fires).

Limited Liability companies are a creation of the state. They originated when the King wanted some major project done (like building London Bridge?) and were limited to the specific project. No doubt some wealthy nobles agreed to do it if the king would limit their liability. As a by-product, it made selling shares in the corporation more attractive to not-so-wealthy individuals, since they weren’t risking their homes as part of the deal. If pension funds couldn’t invest in corporations, creative people would need to invent other ways for us to save for retirement.

You ask, “how would I be protected" from big corporations?  I suspect you think that government is the answer.  But I believe you will find that a government that thinks it needs to solve all our problems will usually find in favour of big business. Politicians may PROMISE to fight for you, to get your vote, but if the company can argue what they are doing is for the common good, your rights will probably not count for much.

You seem to think democracy is a virtue. Consider this. The winning parties in the last federal and provincial elections in Ontario won with less than 40% of the votes cast, and about half of the eligible voters turned out. So about 20% (more or less) of the voters elected the government, which is now free to impose whatever restrictions it thinks are reasonable on the entire population. Maybe that isn’t tyranny in your books, but I don’t see it as a virtue.