It's the crab bucket mentality. Before Bambu Lab 99% of the 3D printer offerings were absolute garbage to the point of not being far from being a scam. You get a CoreXY printer with an enclosure and AMS for a really good price and if you buy their filament in bulk, it is not much more expensive than e.g. Sunlu where buying at least 3 spools per order is mandatory to begin with.

The only way to beat Bambu Lab is to be better than them at the 3D printer game, but most companies can't do that, so people have become resentful while grasping for straws to find things to criticize. Snapmaker got the message and decided to come out with the Snapmaker U1, the rest can wallow in their "open source" superiority complex to silence critics.