Those were gaming rigs though. Pre-builts in that area is always dangerous. They have to add as many features as possible while cutting the price point. Yields are narrow. Kinda like printers, where companies tend to sell them at a loss and make up on toner etc.

Pre-built gaming pcs are also bleeding edge, rush to market. So you're asking for problems.

My understanding is that pricing isn't as competitive in general computing, so they get a better yield, and the products tend to use more stable, legscy components / designs.