The claims and conclusions of this article are merely asserted rather than suported with evidence. (This is true of most of the articles I've seen claiming the opposite as well.)
Gitea wasn't bought, the people running the project held the trademarks and decided to move the trademarks to a new for-profit entity they created in order to provide git related services for some fee structure that isn't clear to me. Largely it's CI/CD service that they are looking to sell.
I don't know if one is better than the other, but knowing that certain libraries are incompatible based on this bifurcation is a good thing to remember.
I think System76 has much less of a perception problem than the others. For Purism, I read much more damming critiques like waiting 3 years for your order. For the others, I nearly never read about them unless I go out of my way to find people discussing them. I would say those are much bigger problems for companies to have.
The criticism is from two angles. First, Clevo is known for products that are not on the high end of the quality spectrum. They don't try to be. Which currently is an obstacle for improving the quality of System76 laptops. System76 however has be working with suppliers to increase the quality of the products and doesn't source everything from Clevo for their laptop lineup. Second, System76 doesn't have the order volume of other brands allowing them to have more control over what their suppliers will supply while keeping per unit costs low enough to satisfy System76 margin expectations and keeping prices attractive enough to customers.
System76 has been making good decisions over time to address these challenges and produce better value for customers. But I don't think it's unfair for people to be critical of the current situation. System76 laptops aren't cheaply priced so customers should expect System76 laptops to meet expectations in line with the prices. Not everyone will agree that System76 is or can do that with their current product offerings.
Unfortunately, the economics of laptop and desktop retail sales has subsidies from software based services built into the price expectations of customers. I like that System76 is moving against those headwinds. It means that System76 is not making decisions to try to get you to sign up for services and respects that the hardware you purchase is for your personal use and gives you autonomy to use it as you'd like without creating hurdles. But it also means their products aren't going to be as compelling to those that are willing to deal with hurdles in exchange for lower prices.
The claims and conclusions of this article are merely asserted rather than suported with evidence. (This is true of most of the articles I've seen claiming the opposite as well.)