There is also another thing where quality Chinese products are very cheap compared to western products. Since Chinese engineers are cheaper, they can live with lower margins on their products.
A roomba was twice as much as a roborock that was better.
Prusa MK4S is 720 EUR, the arguably better Bambu Lab A1 is 260 EUR.
It wasn't labor costs that made the Roomba twice a Roborock, but manufacturing costs. Roomba teardowns basically show that iRobot was just really bad at cost-optimizing their vacuums for mass production.
You can probably maintain your Prusa forever. The Bambu... not so much. It is a philosophy choice here and the 3D printer space is vastly more complex and nuanced for many users than an appliance that has one simple job. Yes if you /just/ want to print stuff and treat it like an appliance as a curious consumer dabbling in the space the Bambu is great. That was never Prusa's target. I don't think the comparison is very strong.
A roomba was twice as much as a roborock that was better.
Prusa MK4S is 720 EUR, the arguably better Bambu Lab A1 is 260 EUR.