The employees invest their time and time is money. The customers invest their money and their trust. The general public invests their tax dollars to create the infrastructure needed for the company to even exist in the first place.

Yes but it is nothing comparable to millions or billions of € invested by shareholder. Sure customer invest their trust and money but they get benefit immediately, aka the product. General public invest their tax for the infrastructure however companies get taxed too for the infrastructure that benefits general public, that's a null equation. Investor are a necessary part of the economy and shall be treated as such, nothing prevent government from taxing more benefits from investment tho.